Image caption The convoy carrying UN chemical weapons inspectors to the sites was targeted by snipers 
 
 Diplomatic pressure on Syria has failed and the UK is considering its response to a suspected chemical attack, Foreign Secretary William Hague says. 
 
 He told the BBC it would be possible for the UK and its allies to respond without the UN's unanimous backing. 
 
 In Syria, UN inspectors visited the site of the suspected attack after their convoy was shot at by snipers. 
 
 The PM is cutting his holiday short and is expected to hold a National Security Council meeting on Wednesday. 
 
 Deputy Prime Minister Nick Clegg has also cancelled a visit to Afghanistan to meet British troops. 
 
 Downing Street said a decision on whether to recall Parliament would be made on Tuesday. 
 
 The suspected chemical attack took place on Wednesday near the Syrian capital Damascus, and reportedly killed more than 300 people. 
 
 Weapons inspectors carried out tests at the scene on Monday after unidentified snipers shot at one of their vehicles, a UN spokesman said. 
 
 Media playback is unsupported on your device Media caption William Hague: UN Security Council has not shouldered its responsibilities 
 
 Mr Hague told BBC Radio 4's Today programme while he could not go into options or a timetable for action, he was not "going to rule anything in or out". 
 
 "We, the United States, many other countries including France, are clear that we can't allow the idea in the 21st century that chemical weapons can be used with impunity," he said. 
 
 A Downing Street spokesman said Prime Minister David Cameron had called Russia's President Vladimir Putin on Monday afternoon to discuss Syria and that they had reiterated the position that the use of chemical weapons should merit a "serious response" from the international community. 
 
 But while Mr Cameron "made clear there was little doubt" the attack was carried out by the Syrian regime, Mr Putin "said they did not have evidence of whether a chemical weapons attack had taken place or who was responsible," the spokesman said. 
 
 MPs are due to return to the Commons on 2 September but there have been demands for Parliament to be recalled. 
 
 Analysis Whitehall officials say no firm decision is likely to be taken on how Britain will respond to last week's alleged chemical attack in Syria until at least Wednesday. That is when David Cameron will be chairing a session of the National Security Council, attended by military and intelligence chiefs and senior ministers. It follows intense consultations between London and Washington with Downing Street keen to stress the two countries are acting in concert. Any military response, if it's decided on, is most likely to be confined to a one-off or limited guided missile strikes on selected Syrian military targets using Tomahawk cruise missiles fired from US Navy warships stationed hundreds of miles away in the eastern Mediterranean. US vessels there are reported to have about 400 such missiles onboard, while a Royal Navy submarine in the region can also carry cruise missiles. But Russia, Syria and Iran have all issued strong warnings against any western military action. 
 
 Labour's shadow foreign secretary Douglas Alexander said he would "expect the prime minister to make his case to Parliament" before a decision was made about UK involvement. 
 
 The prime minister also had phone calls with other leaders, including US President Barack Obama, this weekend, where they agreed on the need to take "strong action". 
 
 He will return several days early from his holiday in Cornwall with his family so he can chair Wednesday's high-level security briefing of senior ministers and defence and intelligence chiefs. 
 
 It is understood the most likely military response would be a one-off or limited guided missile strikes on Syrian military targets fired from US Navy warships, says BBC security correspondent Frank Gardner. 
 
 Prof Michael Clarke, of the Royal United Services Institute, said: "Military advice to politicians in the US and the UK is 'don't think you can dabble in this - you have to go in with both feet'". 
 
 He told the BBC's PM programme limited air strikes might inconvenience the regime but were no guarantee you could stop it. 
 
 Other options - such as a no-fly zone or a safe haven - would have to be led by the US, and at the moment most of the "sabre-rattling" was coming from France and the UK - not the US, he added. 
 
 Whitehall officials have told the BBC the next key decisions would probably be taken at Wednesday's National Security Council meeting. 
 
 'Humanitarian need' 
 
 Mr Hague said diplomatic methods to resolve the civil war in Syria had "failed so far". 
 
 Media playback is unsupported on your device Media caption Russian Foreign Minister Sergei Lavrov: "They [the West] have not been able to come up with any proof but are saying at the same time that the red line has been crossed" 
 
 He said the UN Security Council, split over Syria, had not "shouldered its responsibilities". 
 
 The council is made up of 15 members including permanent members China, Russia, France, the US and the UK which have the power to veto any resolution. 
 
 But any action could be taken "without complete unity on the UN Security Council", he said. 
 
 He said a response could be "based on great humanitarian need and distress" and "in accordance with international law". 
 
 The foreign secretary said the suspected chemical attack was carried out by Syrian President Bashar al-Assad's regime but it blames rebel forces saying footage of the attack was "fabricated". ||||| WASHINGTON/BEIRUT The United States put Syrian President Bashar al-Assad on notice on Monday that it believes he was responsible for using chemical weapons against civilians last week in what Secretary of State John Kerry called a "moral obscenity." 
 
 "President (Barack) Obama believes there must be accountability for those who would use the world's most heinous weapons against the world's most vulnerable people," Kerry said in the most forceful U.S. reaction yet to the August 21 attack. 
 
 Speaking after U.N. chemical weapons experts came under sniper fire on their way to investigate the scene of the attack, White House spokesman Jay Carney said the use of chemical weapons was undeniable and "there is very little doubt in our mind that the Syrian regime is culpable." 
 
 Kerry said Obama was consulting with allies before he decides on how to respond. 
 
 "What we saw in Syria last week should shock the conscience of the world," Kerry told reporters. 
 
 "The indiscriminate slaughter of civilians, the killing of women and children and innocent bystanders by chemical weapons is a moral obscenity. By any standard, it is inexcusable. And despite the excuses and equivocations that some have manufactured, it is undeniable." 
 
 Military chiefs from the United States and its European and Middle Eastern allies met in Jordan for what could be a council of war, should they decide to punish Assad, who has denied using chemical weapons and blamed rebels for staging such attacks. 
 
 Many hundreds of people died in Damascus suburbs in what appears to have been the worst chemical weapons attack since Iraqi leader Saddam Hussein fatally gassed thousands of Kurds in 1988. 
 
 U.N. investigators crossed the front line from the center of the capital, which remains under Assad's control, to inspect the Mouadamiya suburb, one of at least four neighborhoods hit by the poison gas before dawn last Wednesday. 
 
 The United Nations said one vehicle in its convoy was crippled by gunshots fired by "unidentified snipers." The team continued on after turning back for a replacement car. 
 
 Syrian state television blamed rebel "terrorists" for the shooting. The opposition blamed pro-Assad militiamen. 
 
 "I am with the team now," a doctor who uses the name Abu Karam told Reuters by telephone from Mouadamiya. "We are in the Rawda mosque and they are meeting with the wounded. Our medics and the inspectors are talking to the patients and taking samples from the victims now." 
 
 Wassim al-Ahmad, an opposition activist, said members of the Free Syrian Army umbrella rebel organization and the opposition's Mouadamiya Local Council were accompanying the inspectors on their tour of the suburb. 
 
 "The inspectors are now examining victims being treated at a makeshift hospital in Mouadamiya and are taking blood samples from them," Ahmad said. 
 
 INTERVIEWING SURVIVORS 
 
 Video filmed at the site showed inspectors in black and blue body armor and blue U.N. helmets walking through a street as curious onlookers came up to watch. 
 
 They shook hands with men who appeared to be rebels wearing camouflage vests, and were accompanied by doctors and residents. The group descended into the basement of a building where they were told injured survivors were being treated to protect them from more shelling. Another video showed an inspector interviewing a patient and taking notes. 
 
 Activists say at least 80 people were killed in Mouadamiya when the district was hit with poison gas. Hundreds of people also were killed in three other rebel-held districts - Irbin, Ain Tarma and Jobar. 
 
 An opposition activist said a large crowd of people gathered to air their grievances to the U.N. inspectors, who planned to take samples from corpses. 
 
 The inspectors later returned to their hotel and, within an hour, residents reported the shelling of Mouadamiya had resumed. 
 
 The decision to proceed with the mission despite coming under attack thwarted an apparent attempt to halt the inspectors' work before it began. 
 
 "The first vehicle of the Chemical Weapons Investigation Team was deliberately shot at multiple times by unidentified snipers in the buffer zone area," the United Nations said in a statement. "It has to be stressed again that all sides need to extend their cooperation so that the team can safely carry out their important work." 
 
 The inspectors had been stuck in a downtown hotel since the attack, waiting five days for government permission to visit the scene a few miles away. They had arrived three days before the incident, with a mandate to investigate earlier reports of more limited chemical weapons use. 
 
 ASSAD TOO LATE 
 
 Kerry said Assad's decision to finally allow access was too late to be credible. "That is not the behavior of a government that has nothing to hide," Kerry said, adding that Assad's forces had also destroyed evidence by shelling the area. 
 
 "Our sense of basic humanity is offended not only by this cowardly crime, but also by the cynical attempt to cover it up," Kerry said. 
 
 He said the U.N. inspectors could at most confirm that chemical weapons were used, not who used them, but that it was Assad's government that has such weapons and the means of delivering them. He said Washington had additional information on the attack that it would make known soon. 
 
 Washington and its allies say they worry that the time that has elapsed, and continuous shelling by Assad's forces of the affected areas, could make it impossible for the inspectors to collect evidence. The United Nations said Secretary-General Ban Ki-moon was confident the team could get the data it needs. 
 
 Speculation has been mounting that Western countries will order some kind of military response to an incident that took place a year after Obama declared the use of chemical weapons a "red line" that would require strong action. 
 
 With his international credibility seen increasingly on the line, Obama could opt for limited measures such as cruise missile strikes to punish Assad and seek to deter further chemical attacks, without dragging Washington deeper into the war. The United States has started a naval buildup in the region to be ready for Obama's decision. 
 
 In neighboring Israel, citizens have been queuing up for gas masks in case Assad responds to a Western attack by firing on Israel, as Iraq's Saddam did in 1991. 
 
 PHONE CONSULTATIONS 
 
 With tensions rising over Syria, British Prime Minister David Cameron cut short a holiday to lead a top-level security meeting. Obama, Cameron and French President Francois Hollande all spoke to each other and other allies in the past few days in a flurry of phone calls. Cameron also called Russian President Vladimir Putin on Monday. 
 
 Several NATO countries have issued statements pledging a response, although none has been specific about what is planned. 
 
 Top military officers of the United States, Britain, France, other NATO allies and the main anti-Assad countries in the region, including Saudi Arabia and Turkey, met in Jordan on Monday to discuss Syria, diplomats there said. 
 
 The conference was planned but took on new significance because of the latest events, the diplomats said. 
 
 The chairman of the U.S. Joint Chiefs of Staff, Martin Dempsey, a co-host of the meeting with his Jordanian counterpart, has been one of the voices in Washington urging caution and emphasizing the costs of a full-scale military intervention in a war in the heart of the Middle East. 
 
 Obama, who withdrew U.S. troops from Iraq and is winding down the conflict in Afghanistan, is reluctant to involve the United States in another war. A Reuters/Ipsos poll published on Saturday showed about 60 percent of Americans opposed U.S. military intervention, while only 9 percent thought Obama should act. 
 
 ASSAD DEFIANT 
 
 Assad denies the accusations that his forces used chemical weapons and said the United States would be defeated if it intervened in his country. 
 
 "Would any state use chemicals or any other weapons of mass destruction in a place where its own forces are concentrated? That would go against elementary logic," he told the Russian newspaper Izvestia. "Failure awaits the United States as in all previous wars it has unleashed, starting with Vietnam and up to the present day." 
 
 Russia, Assad's main arms supplier and diplomatic defender in the U.N. Security Council, says rebels may have been behind the chemical attack. Foreign Minister Sergei Lavrov said any intervention in Syria without a Security Council resolution would be a grave violation of international law. 
 
 French Foreign Minister Laurent Fabius noted that Russia and China would probably veto a U.N. Security Council vote to allow strikes against Syria. But British Foreign Secretary William Hague said it would still be possible to respond to a chemical weapons attack without the Security Council's permission. 
 
 There are precedents. In 1999 NATO attacked Serbia, a Russian ally, without a Security Council resolution, arguing that action was needed to protect civilians in Kosovo. 
 
 Turkey, a NATO ally and major backer of Syria's opposition, said it would join any international coalition even if a decision for action could not be reached at the United Nations. 
 
 (Additional reporting by Mariam Karouny in Beirut, Khaled Yacoub Oweis in Amman, John Irish in Paris, Katya Golubkova in Moscow, Steve Holland and Paul Eckert in Washington.; Writing by Matt Spetalnick and Claudia Parsons; Editing by Bill Trott and Christopher Wilson) ||||| Story highlights Strikes could be just one chapter in a long war, analyst says 
 
 U.N. inspectors visit scene of reported poison gas attack 
 
 Kerry's remarks indicate a strike is likely, expert says 
 
 A vehicle used by U.N. inspectors was shot at multiple times, U.N. says 
 
 U.N. experts got to inspect the site of a reported chemical attack on civilians near Syria's capital Monday as the United States accused the Syrian government of trying to cover up the attack. 
 
 The U.N. inspectors entered the town of Moadamiyet al-Sham and appeared to be examining the area accompanied by doctors, according to videos posted on social media by Syrian activists. The team had a "very productive" day and will continue its work Tuesday after examining its findings Monday evening, U.N. spokesman Farhan Haq said in New York. 
 
 Government and opposition forces have accused each other of unleashing poison gas last week in the suburban Damascus area of Ghouta. Syria's opposition said that as many as 1,300 people were killed, prompting new calls for Western powers to intervene in the country's 2-year-old civil war. 
 
 In Washington, U.S. Secretary of State John Kerry called the use of chemical weapons a "moral obscenity" that could not go unanswered, and he said Syrian actions are "not the behavior of a government that has nothing to hide." 
 
 Kerry stopped short of directly accusing President Bashar al-Assad's government of a massacre. But he said, "We know that the Syrian regime maintains custody of these chemical weapons. We know that the Syrian regime has the capacity to do this with rockets. We know that the regime has been determined to clear the opposition from those very places where the attacks took place." 
 
 Photos: Unrest in Syria Photos: Unrest in Syria Syrian civil war in photos – In this photo provided by the anti-government activist group Aleppo Media Center, Syrian men help survivors out of a building in Aleppo after it was bombed, allegedly by a Syrian regime warplane on Saturday, February 8. The United Nations estimates more than 100,000 people have been killed since the Syrian conflict began in March 2011. Click through to see the most compelling images taken during the conflict, which is now a civil war: Hide Caption 1 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians gather at a site hit by barrel bombs, allegedly dropped by a regime helicopter on the opposition-controlled Mesekin Hananu district of Aleppo on February 8. Hide Caption 2 of 222 Photos: Unrest in Syria Syrian civil war in photos – Civilians wave national flags as they take part in a rally in support of Syrian President Bashar al-Assad in Damascus, in a handout photo released by the official Syrian Arab News Agency on February 8. Hide Caption 3 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man stands next to debris in the road following a reported airstrike by Syrian government forces in the northern city of Aleppo on February 8. Hide Caption 4 of 222 Photos: Unrest in Syria Syrian civil war in photos – Medical personnel look for survivors after a reported airstrike in Aleppo, Syria, on Saturday, February 1. Hide Caption 5 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians carry a dead body following an airstrike on February 1. Hide Caption 6 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man walks amid debris and dust on January 31. Hide Caption 7 of 222 Photos: Unrest in Syria Syrian civil war in photos – An injured man is covered in dust after an airstrike on January 29. Hide Caption 8 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man tries to fix electrical wires in a neighborhood of Aleppo, Syria, on January 27. Hide Caption 9 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebels and civilians check out a crater that activists say resulted from a Syrian government airstrike on an Aleppo bus station on Tuesday, January 21. Hide Caption 10 of 222 Photos: Unrest in Syria Syrian civil war in photos – Men rush to a site that Syrian government forces reportedly hit in Aleppo on January 21. Hide Caption 11 of 222 Photos: Unrest in Syria Syrian civil war in photos – Buildings lie in ruins in Aleppo on Sunday, January 19, after reported air raids by Syrian government planes. Hide Caption 12 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian child collects items from a garbage pile on Saturday, January 18, in Douma, northeast of the capital. Hide Caption 13 of 222 Photos: Unrest in Syria Syrian civil war in photos – A piece of exploded mortar lies in a street in Daraya, a city southwest of Damascus, on Friday, January 17. Hide Caption 14 of 222 Photos: Unrest in Syria Syrian civil war in photos – Residents search for survivors in Aleppo on Saturday, December 28, 2013, after what activists said were airstrikes by forces loyal to Syrian President Bashar al-Assad. Hide Caption 15 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man appears distraught after an air raid in Aleppo on Monday, December 23. Hide Caption 16 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters sit in a damaged house in Old Aleppo on Saturday, December 21. Hide Caption 17 of 222 Photos: Unrest in Syria Syrian civil war in photos – People search for survivors amid the rubble after an airstrike in Aleppo on Tuesday, December 17. Hide Caption 18 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man sits on the ground after the airstrike in Aleppo on December 17. Hide Caption 19 of 222 Photos: Unrest in Syria Syrian civil war in photos – A woman carries children following airstrikes on a rebel area of Aleppo on Sunday, December 15. Hide Caption 20 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15. Hide Caption 21 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians help a wounded woman following airstrikes in Aleppo on December 15. Hide Caption 22 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15. Hide Caption 23 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebel fighters clash with pro-government forces in Aleppo on Wednesday, December 11. Hide Caption 24 of 222 Photos: Unrest in Syria Syrian civil war in photos – A woman weeps inside a damaged vehicle after forces loyal to President Bashar al-Assad captured the town of Nabak on Monday, December 9. Hide Caption 25 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter takes position during fighting with government forces in Deir Ezzor on Monday, December 2. Hide Caption 26 of 222 Photos: Unrest in Syria Syrian civil war in photos – Shiite fighters from a group called the Hussein Brigade search for rebels from the Free Syrian Army in Hejeira on Thursday, November 21. Hide Caption 27 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army rebels battle government forces in Aleppo on Monday, November 18. Hide Caption 28 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter holds his position in a damaged building during clashes with government forces in Deir Ezzor on Monday, November 11. Hide Caption 29 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter fires during clashes with government forces in Deir Ezzor on November 11. Hide Caption 30 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter prepares an improvised mortar shell in Aleppo, Syria, on Saturday, November 9. Hide Caption 31 of 222 Photos: Unrest in Syria Syrian civil war in photos – Two injured men are transported on a cart in Aleppo, Syria, following shelling as fighting between pro-government forces and rebels continues on Saturday, October 26. Hide Caption 32 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebel fighters hold a position in Deir Ezzor, Syria, on Thursday, October 24. Hide Caption 33 of 222 Photos: Unrest in Syria Syrian civil war in photos – An opposition fighter stands in the doorway of a building as he smokes a cigarette in Deir Ezzor, Syria, on Tuesday, October 22. Hide Caption 34 of 222 Photos: Unrest in Syria Syrian civil war in photos – People use buckets as they try to extinguish a fire that ignited at a fuel station in Aleppo, Syria, on Sunday, October 20. Hide Caption 35 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian opposition fighter aims a catapult toward regime forces in Aleppo, Syria, on Thursday, October 17. Hide Caption 36 of 222 Photos: Unrest in Syria Syrian civil war in photos – Firefighters extinguish a burning vehicle after two mortar rounds struck the Abu Roumaneh area in Damascus, Syria, on Saturday, October 12. Hide Caption 37 of 222 Photos: Unrest in Syria Syrian civil war in photos – An opposition fighter aims as others run for cover while they hold a position behind burning tires in the Salaheddin district of the northern Syrian city of Aleppo on Wednesday, October 9. Hide Caption 38 of 222 Photos: Unrest in Syria Syrian civil war in photos – An opposition fighter smokes a cigarette as he takes a break following the injury of his friend in the Salaheddin neighborhood of Aleppo on October 9. Hide Caption 39 of 222 Photos: Unrest in Syria Syrian civil war in photos – Smoke rises after a mortar shell hit a residential area during fighting between Syrian government forces and rebels in Maaret al-Numan, Syria, on October, 9. Hide Caption 40 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebel fighters cover a car in mud for camouflage at an undisclosed location in Syria's northwestern province of Idlib on Tuesday, October 8. Hide Caption 41 of 222 Photos: Unrest in Syria Syrian civil war in photos – Masked female rebel fighters walk alongside their trainer on a street in the Salaheddin district of Aleppo, Syria, on October 8. Hide Caption 42 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter prays moments before heading into battle in Maaret al-Numan, Syria, on Monday, October 7. Hide Caption 43 of 222 Photos: Unrest in Syria Syrian civil war in photos – A mother comforts her baby in an area where she and her family have taken shelter after fleeing their village turned battlefield in Syria's Idlib province on Sunday, September 22. Hide Caption 44 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man checks an AK-47 at his gun shop in Aleppo, Syria, on Saturday, September 21. Hide Caption 45 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters take cover moments after firing a rocket toward government forces in the Idlib province of northern Syria on Friday, September 20. Hide Caption 46 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebel fighters inspect a stairwell amid fighting against Syrian government forces on Thursday, September 19, in the Saif al-Dawla district of Aleppo, Syria. Hide Caption 47 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian child sits in a village in the Idlib province countryside on September 19. Hide Caption 48 of 222 Photos: Unrest in Syria Syrian civil war in photos – Opposition fighters react after returning from the battlefield in the Idlib province countryside on September 19. Hide Caption 49 of 222 Photos: Unrest in Syria Syrian civil war in photos – Smoke rises after a bomb was thrown from a helicopter, hitting a rebel position during heavy fighting between troops loyal to Syrian President Bashar al-Assad and opposition fighters in the Idlib province on September 19. Hide Caption 50 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebel fighters duck behind a barricade from firing in Aleppo on Wednesday, September 18. Hide Caption 51 of 222 Photos: Unrest in Syria Syrian civil war in photos – AFP reporter Sammy Ketz hits the ground as a Syrian soldier runs past during sniper fire in Maalula on September 18. Ketz and a photographer were reporting on the ancient Christian Syrian town northeast of Damascus. Hide Caption 52 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian opposition fighter takes a break on a mountain near a rebel camp in Idlib province on September 18. Hide Caption 53 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter rests inside a cave at a rebel camp in Idlib province on Tuesday, September 17. Hide Caption 54 of 222 Photos: Unrest in Syria Syrian civil war in photos – Volunteers wear protective gear to show a class how to respond to a chemical attack in Aleppo, Syria, on September 15. For two months, Mohammad Zayed, an Aleppo University student, has been training a group of 26 civilians to respond to a chemical attack. Hide Caption 55 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syria's pro-Assad militia rest near Maalula, Syria, on Friday, September 13. Hide Caption 56 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian soldiers take aim at rebel fighters positioned in the mountains of the Christian town of Maalula on September 13. Hide Caption 57 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebels parade at a former military academy north of Aleppo during a September 13 ceremony to mark an agreement to unite two rebel brigade forces. Hide Caption 58 of 222 Photos: Unrest in Syria Syrian civil war in photos – A fighter of the Popular Front for the Liberation of Palestine General Command squats next to the covered body of an alleged foreign rebel fighter in the Yarmouk refugee camp in the Syrian capital of Damascus on Thursday, September 12. Hide Caption 59 of 222 Photos: Unrest in Syria Syrian civil war in photos – An opposition fighter runs in front of a sniper curtain in the industrial area of Deir Ezzor, Syria, during clashes with regime forces on September 12. Hide Caption 60 of 222 Photos: Unrest in Syria Syrian civil war in photos – A sheet hangs across an alley way to shield fighters from sniper fire as a fighter of the Popular Front for the Liberation of Palestine General Command walks past destroyed buildings in the Yarmouk refugee camp in Damascus, Syria, on September 12. Hide Caption 61 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter stands guard inside a damaged house in Aleppo's Qastal al-Harami neighborhood on September 11. Hide Caption 62 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters climb a flight of stairs to take positions near the Hanano barracks on September 11. Hide Caption 63 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian government tank is seen during clashes with Free Syrian Army fighters in Maaloula, Syria, on September 11. Hide Caption 64 of 222 Photos: Unrest in Syria Syrian civil war in photos – A funeral is held on September 11 for three Christian Syrians killed during battles with an al Qaeda-linked rebel group that took control of the historic Christian town of Maaloula from regime forces during the weekend. Hide Caption 65 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man walks through a destroyed residential area of Saraqib, Syria, on Monday, September 9, following repeated airstrikes by government forces. Hide Caption 66 of 222 Photos: Unrest in Syria Syrian civil war in photos – A soldier wears a picture of Syrian President Bashar al-Assad on his chest while at a market in old Damascus on September 8. Hide Caption 67 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter prays in a trench in the Damascus suburbs on September 8. Hide Caption 68 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter takes up a shooting position in Aleppo on September 8. Hide Caption 69 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter runs for cover in Raqqa province on September 8. Hide Caption 70 of 222 Photos: Unrest in Syria Syrian civil war in photos – Buildings are heavily damaged in the Salah al-Din area of Aleppo on September 8. Hide Caption 71 of 222 Photos: Unrest in Syria Syrian civil war in photos – A boy named Issa , 10, carries a mortar shell in a weapons factory of the Free Syrian Army in Aleppo on Saturday, September 7. The boy works with his father in the factory. Hide Caption 72 of 222 Photos: Unrest in Syria Syrian civil war in photos – Issa fixes a mortar launcher in the Aleppo weapons factory on September 7. Hide Caption 73 of 222 Photos: Unrest in Syria Syrian civil war in photos – A bedroom lies in ruins after clashes between government forces and rebels around Ariha on September 7. Hide Caption 74 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian forces are seen in the Syrian Christian town of Maaloula on September 7. Hide Caption 75 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian soldier prepares large-caliber bullets for a machine gun in Maaloula on September 7. Hide Caption 76 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man stands inside a home damaged by heavy shelling in Arbeen, a suburb of Damascus, Syria, on September 7. Hide Caption 77 of 222 Photos: Unrest in Syria Syrian civil war in photos – Men gather on the remains of a destroyed building after reported airstrikes by Syrian government forces in the rebel-held northwestern Syrian province of Idlib on Thursday, September 5. Hide Caption 78 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter takes cover as he watches forces loyal to President Bashar al-Assad near Hanano barracks in Aleppo on September 3. Hide Caption 79 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters walk inside a damaged house in Aleppo on September 3. Hide Caption 80 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters talk inside a burnt house in Aleppo on September 3. Hide Caption 81 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter peeks through the curtains of a bedroom in Deir ez-Zor, Syria, on Monday, September 2. Hide Caption 82 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters take their positions behind piled sandbags, as one of them points his weapon, in Deir ez-Zor on September 2. Hide Caption 83 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter points his weapon at Syrian regime forces in Deir ez-Zor on September 2. Hide Caption 84 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian firefighters try to extinguish a fire after a missile hit a residential building in Damascus, Syria, on September 2. Hide Caption 85 of 222 Photos: Unrest in Syria Syrian civil war in photos – A U.N. arms expert collects samples during an inspection of a suspected chemical weapons strike site in the Ghouta area outside Damascus on August 29. Hide Caption 86 of 222 Photos: Unrest in Syria Syrian civil war in photos – People search for belongings in rubble in Raqqa, Syria, on August 29. Hide Caption 87 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters launch a rocket toward forces loyal to Syrian President Bashar al-Assad in Deir Ezzor on August 29. Hide Caption 88 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian Kurd uses hay to hide another woman in a training session organized by the Kurdish Women's Defense Units on Wednesday, August 28, in a northern Syrian border village. They're preparing if the area comes under attack. Hide Caption 89 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters escort U.N. vehicles with chemical weapons experts on August 28 through a site of a suspected chemical weapons attack outside Damascus. Hide Caption 90 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter takes position behind sandbags in the old city of Aleppo, Syria, on Tuesday, August 27. Hide Caption 91 of 222 Photos: Unrest in Syria Syrian civil war in photos – A U.N. team leaves its Damascus, Syria, hotel in a convoy on Monday, August 26. The team was to investigate an alleged chemical attack that killed hundreds last week in a suburb of the Syrian capital. Sniper fire hit a vehicle used by the U.N. chemical weapons investigation team multiple times Monday, according to the United Nations. Hide Caption 92 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian soldier walks down a street in Damascus on Saturday, August 24. Hide Caption 93 of 222 Photos: Unrest in Syria Syrian civil war in photos – Pigeons lie dead on the ground on August 24 from after what activists say is the use of chemical weapons by government forces in the Damascus suburb of Arbeen. Hide Caption 94 of 222 Photos: Unrest in Syria Syrian civil war in photos – Columns of smoke rise in Barzeh after heavy shelling on Friday, August 23. Hide Caption 95 of 222 Photos: Unrest in Syria Syrian civil war in photos – A young Free Syrian Army fighter is reflected in a mirror as he takes position in a house in Aleppo on Thursday, August 22. Hide Caption 96 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebels move around a building in Aleppo on August 22. Hide Caption 97 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels claim pro-government forces used chemical weapons to kill citizens outside Damascus on Wednesday, August 21. People inspect bodies in this photo released by the Syrian opposition Shaam News Network. Hide Caption 98 of 222 Photos: Unrest in Syria Syrian civil war in photos – People search the rubble of a bombed building in Aleppo, Syria, on Friday, August 16. Hide Caption 99 of 222 Photos: Unrest in Syria Syrian civil war in photos – Men bury the bodies of six members of the same family killed in a bombing in Raqqa on Saturday, August 10. Hide Caption 100 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian Army soldiers patrol a devastated street in Homs on Wednesday, July 31. Hide Caption 101 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters move through a hole in a wall in Khan al-Assal on Monday, July 22, after seizing the town. Hide Caption 102 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter walks past swings in a deserted playground in Deir al-Zor, Syria, on Sunday, July 21. Hide Caption 103 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter speaks with a fellow fighter through a hole in a wall in Deir al-Zor on July 21. Hide Caption 104 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter casts a shadow on a wall as he carries his weapon in a shelter in Deir al-Zor on Thursday, July 18. Hide Caption 105 of 222 Photos: Unrest in Syria Syrian civil war in photos – Yahya Sweed, 13, is comforted by his father as he lies on a bed in Kfar Nubul on Tuesday, July 16. The boy was injured by shrapnel, resulting in the amputation of his right leg. Hide Caption 106 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter naps in a trench about 300 feet from the Syrian government forces' positions along the highway connecting Idlib with Latakia on Monday, July 15. Hide Caption 107 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter uses a hole in the wall of a destroyed school to aim at Syrian government forces in the Izaa district of Aleppo on Sunday, July 14. Hide Caption 108 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter uses a mirror to scope out snipers loyal to Syrian President Bashar al-Assad in Aleppo on Friday, July 12. Hide Caption 109 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter stands over a boy who was injured during shelling in Al-Bara on Monday, July 8. Hide Caption 110 of 222 Photos: Unrest in Syria Syrian civil war in photos – Members of the Free Syrian Army fire a homemade rocket toward regime forces in Deir al-Zor on Sunday, June 16. Hide Caption 111 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels leave their position in the northwestern town of Maaret al-Numan on Thursday, June 13. The White House said that the Syrian government has crossed a "red line" with its use of chemical weapons and announced it would start arming the rebels. Hide Caption 112 of 222 Photos: Unrest in Syria Syrian civil war in photos – Forces loyal to Syrian President Bashar al-Assad are seen near Qusayr on Thursday, May 30. Hide Caption 113 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels take position in a house during clashes with regime forces in the old city of Aleppo on May 22. Hide Caption 114 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian army soldiers take control of the village of Western Dumayna north of the rebel-held city of Qusayr on Monday, May 13. Syrian troops captured three villages in Homs province, allowing them to cut supply lines to rebels inside Qusayr town, a military officer told AFP. Hide Caption 115 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebel fighters fire at government forces in the northern Syrian city of Aleppo on Sunday, May 12. Hide Caption 116 of 222 Photos: Unrest in Syria Syrian civil war in photos – Searchers use a flashlight as they look for survivors among the rubble created by what activists say was a missile attack from the Syrian regime, in Raqqa province, Syria, on April 25. Hide Caption 117 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Kurdish fighter from the "Popular Protection Units" (YPG) takes position inside a building in the majority-Kurdish Sheikh Maqsood area of Aleppo, on Apri. 21. Hide Caption 118 of 222 Photos: Unrest in Syria Syrian civil war in photos – People walk past destroyed houses in the northern Syrian town of Azaz on Sunday, April 21. Hide Caption 119 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters take positions prior to an offensive against government forces in the Khan al-Assal area, near Aleppo on Saturday, April 20. Hide Caption 120 of 222 Photos: Unrest in Syria Syrian civil war in photos – Men inspect damage at a house destroyed in an airstrike in Aleppo on April 15. Hide Caption 121 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian and Kurdish rebel fighters walk in the Sheikh Maqsud district of Aleppo on April 14. Hide Caption 122 of 222 Photos: Unrest in Syria Syrian civil war in photos – A female rebel monitors the movement of Syrian government forces in Aleppo's Sheikh Maqsud neighborhood on Thursday, April 11. Hide Caption 123 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel runs to avoid sniper fire from Syrian government forces in Aleppo on April 11. Hide Caption 124 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels observe the movement of Syrian government forces around Al-Kendi hospital in Aleppo on Wednesday, April 10. Hide Caption 125 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rescue teams and security forces check out the scene of a deadly car bomb explosion in Damascus on April 8. Hide Caption 126 of 222 Photos: Unrest in Syria Syrian civil war in photos – The fighting has taken a toll on buildings in Aleppo's Saladin district, seen here on April 8. Hide Caption 127 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel runs for cover in Deir ez-Zor on April 2. Hide Caption 128 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel checks for snipers across the street toward the Citadel in Aleppo, Syria, on Saturday, March 30, in this photo taken by iReporter Lee Harper. Hide Caption 129 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian fighter mourns the death of a friend in Aleppo on March 30, in this photo taken by iReporter Lee Harper. Hide Caption 130 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian opposition fighter runs for cover from Syrian army snipers in Aleppo on Wednesday, March 27. Hide Caption 131 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian girl covers her face to protect herself from fumes as a street covered with uncollected garbage is fumigated in Aleppo on Sunday, March 24. Hide Caption 132 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian man and his family drive past damaged buildings in Maarat al-Numan, on Wednesday, March 20. Hide Caption 133 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians carry the body of a Syrian army soldier during a funeral ceremony in Idlib province on Tuesday, March 19. Hide Caption 134 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels take position in Aleppo, the largest city in the country, on March 11. Hide Caption 135 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian men search for their relatives amongst the bodies of civilians executed and dumped in the Quweiq River on March 11. Hide Caption 136 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter looks back as smoke rises during fighting between rebel fighters and forces loyal to Syria's President Bashar al-Assad on the outskirts of Aleppo on Saturday, March 2. Hide Caption 137 of 222 Photos: Unrest in Syria Syrian civil war in photos – Residents read Shaam News newspapers published by the Free Syrian Army in Aleppo on March 2. Hide Caption 138 of 222 Photos: Unrest in Syria Syrian civil war in photos – A member of the Free Syrian Army reacts to the death of a comrade who was killed in fighting, at Bustan al Qasr cemetery in Aleppo on Friday, March 1. Hide Caption 139 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter throws a home-made grenade at Syrian government forces in Aleppo on February 16. Hide Caption 140 of 222 Photos: Unrest in Syria Syrian civil war in photos – A member of the Free Syrian Army stands with his weapon as he looks at a rainbow in Aleppo on February 16. Hide Caption 141 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian woman looks through a bus window in Aleppo on February 14. Hide Caption 142 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters walk through a dust-filled stairwell in Damascus on February 7. Hide Caption 143 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel gestures at comrades from inside a broken armored personnel carrier in Al-Yaqubia on February 6. Hide Caption 144 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter throws a hand grenade inside a Syrian Army base in Damascus on February 3. Hide Caption 145 of 222 Photos: Unrest in Syria Syrian civil war in photos – People stand in the dust of a building destroyed in an airstrike in Aleppo, Syria on February 3. Hide Caption 146 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters run as they enter a Syrian Army base during heavy fighting in the Arabeen neighborhood of Damascus on February 3. Hide Caption 147 of 222 Photos: Unrest in Syria Syrian civil war in photos – An unexploded mortar shell fired by the Syrian Army sits lodged in the ground in Damascus on January 25. Hide Caption 148 of 222 Photos: Unrest in Syria Syrian civil war in photos – Fighters from Fateh al Sham unit of the Free Syrian Army fire on Syrian Army soldiers at a check point in Damascus on January 20. Hide Caption 149 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army fighter walks between buildings damaged during Syrian Air Force strikes in Damascus on January 19. Hide Caption 150 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel fighter tries to locate a government jet fighter in Aleppo on January 18. Hide Caption 151 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels launch a missile near the Abu Baker brigade in Albab on January 16. Hide Caption 152 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian boy walks near rubbish next to tents at a refugee camp near the northern city of Azaz on the Syria-Turkey border, on January 8. Hide Caption 153 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians look for survivors amid the rubble of a building targeted by a missile in Aleppo on January 7. Hide Caption 154 of 222 Photos: Unrest in Syria Syrian civil war in photos – A father reacts after hearing of a shelling by forces loyal to Syria's President Bashar al-Assad in Aleppo on January 3. Hide Caption 155 of 222 Photos: Unrest in Syria Syrian civil war in photos – A patient smokes a cigarette at Dar Al-Ajaza psychiatric hospital in Aleppo on December 18, 2012. The psychiatric ward, housing around 60 patients, has lacked the means to function properly since fighting broke out there in July. Hide Caption 156 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians mourn a fallen rebel fighter at a rebel base in the al-Fardos area of Aleppo on December 8, 2012. Hide Caption 157 of 222 Photos: Unrest in Syria Syrian civil war in photos – Members of Liwa (Brigade) Salahadin, a Kurdish military unit fighting alongside rebel fighters, monitor the area in the besieged district of Karmel al-Jabl in Aleppo on December 6, 2012. Hide Caption 158 of 222 Photos: Unrest in Syria Syrian civil war in photos – A member of Liwa Salahadin aims at a regime fighter in the besieged district of Karmel al-Jabl in Aleppo on December 6, 2012. Hide Caption 159 of 222 Photos: Unrest in Syria Syrian civil war in photos – Two young boys sit underneath a washline in a refugee camp on the border between Syria and Turkey near Azaz on December 5, 2012. Hide Caption 160 of 222 Photos: Unrest in Syria Hide Caption 161 of 222 Photos: Unrest in Syria Syrian civil war in photos – The bodies of three children, who were allegedly killed in a mortar shell attack that landed close to a bakery in Aleppo, on December 2, 2012, are laid out for identification by family members at a makeshift hospital at an undisclosed location of the city. Hide Caption 162 of 222 Photos: Unrest in Syria Syrian civil war in photos – Smoke rises in the Hanano and Bustan al-Basha districts in Aleppo on December 1, 2012 as fighting continues through the night. Hide Caption 163 of 222 Photos: Unrest in Syria Syrian civil war in photos – Damaged houses in Aleppo are seen after an airstrike on November 29, 2012. Hide Caption 164 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel mourns the death of a comrade in Maraat al-Numan on November 20, 2012. Hide Caption 165 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians protesters stand on Assad's portrait during an anti-regime demonstration in Aleppo on November 16, 2012. Hide Caption 166 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel takes cover during fighting against Syrian government forces in Aleppo on November 15, 2012. Hide Caption 167 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian opposition fighter Bazel Araj, 19, sleeps next to his pistol in Aleppo on November 11, 2012. Hide Caption 168 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter fires at a Syrian government position in Aleppo on November 6, 2012. Hide Caption 169 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel leaps over debris left in the street while running across a "sniper alley" near the Salahudeen district in Aleppo on November 4, 2012. Hide Caption 170 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebels hold their position in the midst of a battle on November 3, 2012 in Aleppo. Hide Caption 171 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man cries while being treated in a local hospital in a rebel-controlled area of Aleppo on October 31, 2012. Hide Caption 172 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man is treated for wounds after a government jet attacked the Karm al-Aser neighborhood in eastern Aleppo on October 31, 2012. Hide Caption 173 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel interrogates a handcuffed and blindfolded man suspected of being a pro-regime militiaman in Aleppo on October 26, 2012. Hide Caption 174 of 222 Photos: Unrest in Syria Syrian civil war in photos – Smoke rises from a fuel station following a mortar attack as Syrian women walk on a rainy day in the Arqub neighborhood of Aleppo on October 25, 2012. Hide Caption 175 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel fires at an army position in the Karm al-Jabal district of Aleppo on October 22, 2012. Hide Caption 176 of 222 Photos: Unrest in Syria Syrian civil war in photos – A wounded Syrian boy sits on the back of a truck carrying victims and wounded people to a hospital following an attack by regime forces in Aleppo on October 21, 2012. Hide Caption 177 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man lies on the ground after being shot by a sniper for a second time as he waits to be rescued by members of the Al-Baraa Bin Malek Battalion, part of the Free Syria Army's Al-Fatah brigade, in Aleppo on October 20, 2012. Hide Caption 178 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian army soldiers run for cover during clashes with rebel fighters at Karam al-Jabal neighborhood of Aleppo on October 20, 2012. Hide Caption 179 of 222 Photos: Unrest in Syria Syrian civil war in photos – Smoke rises after a Syrian Air Force fighter jet fired missiles at the suburbs of the northern province of Idlib on October 16, 2012. Hide Caption 180 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian opposition fighter stands near a post in Aleppo on October 11, 2012. Hide Caption 181 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian man mourns the death of his father, who was killed during a government attack in Aleppo on October 10, 2012. Hide Caption 182 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel fighter is carried by his friends and laid on a gurney to be treated for gunshot wounds sustained during heavy battles with government forces in Aleppo on October 1, 2012. Hide Caption 183 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels help a wounded comrade to an Aleppo hospital after he was injured in a Syrian army strike on September 18, 2012. Hide Caption 184 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syria Army fighters are reflected in a mirror they use to see a Syrian Army post only 50 meters away in Aleppo on September 16, 2012. Hide Caption 185 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian man carrying grocery bags tries to dodge sniper fire as he runs through an alley near a checkpoint manned by the Free Syria Army in Aleppo on September 14, 2012. Hide Caption 186 of 222 Photos: Unrest in Syria Syrian civil war in photos – A woman walks past a destroyed building in Aleppo on September 13, 2012. Hide Caption 187 of 222 Photos: Unrest in Syria Syrian civil war in photos – Free Syrian Army fighters battle during street fighting against Syrian army soldiers in Aleppo on September 8, 2012. Hide Caption 188 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian man wounded by shelling sits on a chair outside a closed shop in Aleppo on September 4, 2012. Hide Caption 189 of 222 Photos: Unrest in Syria Syrian civil war in photos – A woman sits in her wheelchair next to her house, damaged by a Syrian air raid, near Homs on August 26, 2012. Hide Caption 190 of 222 Photos: Unrest in Syria Syrian civil war in photos – Members of the Free Syrian Army clash with Syrian army soliders in Aleppo's Saif al-Dawla district on August 22, 2012. Hide Caption 191 of 222 Photos: Unrest in Syria Hide Caption 192 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man mourns in front of a field hospital on August 21, 2012 in Aleppo. Hide Caption 193 of 222 Photos: Unrest in Syria Hide Caption 194 of 222 Photos: Unrest in Syria Syrian civil war in photos – Wounded civilians wait in a field hospital after an air strike on August 21, 2012 in Aleppo. Hide Caption 195 of 222 Photos: Unrest in Syria Syrian civil war in photos – People pray during the funeral of a Free Syrian Army fighter, Amar Ali Amero, on August 21, 2012. Hide Caption 196 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man cries near the graves of his two children killed during a recent Syrian airstrike in Azaz on August 20, 2012. Hide Caption 197 of 222 Photos: Unrest in Syria Hide Caption 198 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian woman holds her dead baby as she screams upon seeing her husband's body being covered following an airstrike by regime forces on the town of Azaz on August 15, 2012. Hide Caption 199 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian rebel runs in a street of Selehattin during an attack on the municipal building on July 23, 2012. Hide Caption 200 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels hunt for snipers after attacking the municipality building in the city center of Selehattin on July 23, 2012. Hide Caption 201 of 222 Photos: Unrest in Syria Syrian civil war in photos – Members of the Free Syrian Army's Mugaweer (commandos) Brigade pay their respects in a cemetery on May 12, 2012 in Qusayr. Hide Caption 202 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian rebels take position near Qusayr on May 10, 2012. Hide Caption 203 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army member takes cover in underground caves in Sarmin on April 9, 2012. Hide Caption 204 of 222 Photos: Unrest in Syria Syrian civil war in photos – Rebels prepare to engage government tanks that advanced into Saraquib on April 9, 2012. Hide Caption 205 of 222 Photos: Unrest in Syria Syrian civil war in photos – Men say prayers during a ceremony in Binnish on April 9, 2012. Hide Caption 206 of 222 Photos: Unrest in Syria Syrian civil war in photos – A young boy plays with a toy gun in Binnish on April 9, 2012. Hide Caption 207 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Free Syrian Army rebel mounts his horse in the Al-Shatouria village near the Turkish border in northwestern Syria on March 16, 2012, a year after the uprising began. Hide Caption 208 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian refugees walk across a field before crossing into Turkey on March 14, 2012. Hide Caption 209 of 222 Photos: Unrest in Syria Syrian civil war in photos – A rebel takes position in Al-Qsair on January 27, 2012. Hide Caption 210 of 222 Photos: Unrest in Syria Syrian civil war in photos – A protester in Homs throws a tear gas bomb back towards security forces, on December 27, 2011. Hide Caption 211 of 222 Photos: Unrest in Syria Syrian civil war in photos – A man stands under a giant Syrian flag outside the Umayyad Mosque in Damascus on December 24, 2011. Hide Caption 212 of 222 Photos: Unrest in Syria Syrian civil war in photos – A member of the Free Syrian Army looks out over a valley in the village of Ain al-Baida on December 15, 2011. Hide Caption 213 of 222 Photos: Unrest in Syria Syrian civil war in photos – Members of the Free Syrian Army stand in an valley near the village of Ain al-Baida, close to the Turkish border, on December 15, 2011. Hide Caption 214 of 222 Photos: Unrest in Syria Syrian civil war in photos – Displaced Syrian refugees walk through an orchard adjacent to Syria's northern border with Turkey on June 14, 2011, near Khirbet al-Jouz. Hide Caption 215 of 222 Photos: Unrest in Syria Syrian civil war in photos – A Syrian man holds up a portrait of President Bashar al-Assad during a rally to show support for the president in Damascus on April 30, 2011. Hide Caption 216 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians rally to show their support for President Bashar al-Assad in Damascus on April 30, 2011. Hide Caption 217 of 222 Photos: Unrest in Syria Syrian civil war in photos – A screen grab from YouTube shows thick smoke rising above as Syrian anti-government protesters demonstrate in Moaret Al-Noman on April 29, 2011. Hide Caption 218 of 222 Photos: Unrest in Syria Syrian civil war in photos – A screen grab from YouTube shows Syrian anti-government protesters run for cover from tear gas fired by security forces in Damascus on April 29, 2011, during the "Day of Rage" demonstrations called by activists to put pressure on al-Assad. Hide Caption 219 of 222 Photos: Unrest in Syria Syrian civil war in photos – A woman sits by the hospital bed of a man allegedly injured when an armed group seized rooftops in Latakia on March 27, 2011, and opened fire at passers-by, citizens and security forces personnel according to official sources. Hide Caption 220 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrians wave their national flag and hold portraits of al-Assad during a rally to show their support for their leader in Damascus on March 29, 2011. Hide Caption 221 of 222 Photos: Unrest in Syria Syrian civil war in photos – Syrian protesters chant slogans in support of al-Assad during a rally in Damascus on March 25, 2011. Hide Caption 222 of 222 
 
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 Meanwhile, he said that Syria was "systemically destroying evidence" of last week's attack by continuing to shell the area and that the danger the team faced Monday "only further weakens the regime's credibility." The Obama administration is now weighing how to respond in talks with U.S. allies and members of Congress, he said. 
 
 "Nothing today is more serious, and nothing is receiving more serious scrutiny," Kerry said. 
 
 Monday's examination took place after unidentified snipers shot multiple times at a vehicle used by the U.N. team and after an explosion near the site inspectors planned to visit, the United Nations said. There were no reports of injuries. 
 
 U.N. officials did not say who was behind the shooting or the explosion, which witnesses said may have been caused by a mortar shell. The Syrian government accused "terrorists" of firing on the inspectors, Syrian state TV reported. 
 
 U.N. Secretary-General Ban Ki-moon said inspectors visited hospitals, interviewed witnesses, survivors and doctors and collected some samples. Speaking from Seoul, South Korea, Ban said he has directed the group to register a "strong complaint" to government and opposition forces to make sure the team's safety is guaranteed. 
 
 The Syrian government agreed to grant the inspectors full access on Sunday, pledging to cease all hostilities as long as the team was on the ground, the United Nations said. And an umbrella group for the Syrian opposition, the Syrian National Coalition, said rebel forces would ensure the safety of any U.N. personnel in the area. 
 
 But the government would not let U.N. inspectors approach the site for days, and the team feared that the chemical evidence may have dissipated. 
 
 Attacks could reinforce poison gas 'taboo' 
 
 Middle East analyst Richard Haass told CNN's The Lead that Kerry's comments "went far out on a limb" and indicate that a U.S. strike on Syria was in the works, with or without U.N. Security Council backing. Haass, the president of the Council on Foreign Relations, said military action was needed "to underscore the principle, the norm, the taboo that these weapons ought to have." 
 
 "No one, Syria or anybody else, now and forevermore, should be able to use such weapons, much less biological or nuclear weapons, with impunity," he said. But he said Washington should limit its intervention in the conflict, "so we don't get enmeshed in what I think could become a quagmire." 
 
 "If we want to help the opposition, the best way to do it is through considerable arming of those elements of the opposition with agendas we can support," he said. 
 
 But with Syria already seen as a proxy war that has been spilling across its neighbors' borders for months, the prospects for improvement aren't likely to be aided by American airstrikes, said Andrew Tabler, a senior fellow at the Washington Institute for Near East Policy. 
 
 "This is just going to be one chapter in a very long struggle we have in Syria," Tabler told CNN's The Situation Room. 
 
 Russia, Syria's leading ally, has raised sharp objections to the possibility of any outside intervention. Foreign Minister Sergey Lavrov said Monday that reports of the use of chemical weapons must be "thoroughly and professionally investigated" and submitted to the U.N. Security Council. 
 
 At a news conference Monday, Lavrov said there's no proof yet that the Syrian government was involved in last week's reported attack. And Sunday, a Foreign Ministry statement compared the Western allegations against Syria to the claims that Iraq was hoarding weapons of mass destruction before the U.S. invasion in 2003 -- claims that fell apart once American troops began searching for them. 
 
 Charles Duelfer, the former head of U.S. weapons inspection teams in Iraq, said the U.N. experts will be looking to collect evidence from witnesses and survivors of last week's attack, including samples that can be analyzed later. 
 
 "They'll be looking for remnants of the munitions, which could be sophisticated munitions that a military would have -- or if it turns out, unexpectedly, to be the case that the insurgents had cobbled together some sort of CW capability, maybe they'll find that," Duelfer said. 
 
 Duelfer said he expects the U.S. government has its own sources: "Presumably, the National Security Agency can listen to people besides the United States, so they may have data which the weapons inspectors may not have," he told The Situation Room. But while Washington's evidence may be solid, U.N. inspectors "provide credibility across the board." 
 
 "When they say something, presumably all countries will say. 'OK, we can accept that, they don't have a dog in that fight,' " Duelfer said. 
 
 U.S. officials have said they have no credible evidence pointing to opposition groups using chemical weapons. And the Obama administration is expected to declassify the intelligence assessment backing up its assertion that the Syrian regime was responsible for last week's attack before any U.S. military action would take place, a senior administration official said Monday. 
 
 That evidence "includes but is not limited to" satellite images of activity at Syrian military installations identified as including chemical weapons depots, a senior administration official familiar with the intelligence told CNN. 
 
 And Kerry said he had argued to Syrian Foreign Minister Walid Moallem last week that if the government had nothing to hide, "then their response should be immediate: immediate transparency, immediate access, not shelling." 
 
 "Failure to permit that, I told him, would tell its own story," he said. 
 
 Al-Assad: It wasn't us 
 
 The Pentagon has sent four warships armed with cruise missiles to the region, and Obama will be presented with final options regarding actions against Syria in the next few days, a senior administration official said Monday. 
 
 But as U.S. muscle plows the waters of the eastern Mediterranean Sea, al-Assad on Monday repeated his government's denial that his army had anything to do with the use of poison gas. 
 
 "The area of the claimed attack is in contiguity with the Syrian army positions, so how is it possible that any country would use chemical weapons in an area where its own forces are located?" he asked in an interview with Russian newspaper Izvestia. 
 
 Al-Assad accused the United States, Britain and France of exploiting the incident by trying to verify rebel allegations instead of verifying facts. 
 
 The use of a large amount of chemical weapons would cross a "red line" and threaten U.S. interests in the region, Obama announced last year. Tabler, who has had extensive contacts with al-Assad, said the Syrian leader may have watched as Washington reacted cautiously to previous reports of chemical warfare and gambled incorrectly that last week's attack would draw a similar response. 
 
 "I think he thought that he could push the envelope again and that he could actually show his own people that no one is going to come to their rescue," Tabler said. 
 
 Opposition accusations 
 
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 Opposition members say rockets with chemical payloads were among the ordnance government troops unleashed at the rebel stronghold of Ghouta early Wednesday. More than 1,300 people died, most of them by gas, according to opposition spokesman Khaled al-Saleh. 
 
 The opposition backed up the allegations with gruesome video of rows of dead bodies, including women and children. They had no visible wounds, and some appeared to be bloated. The aid agency Medecins sans Frontieres said three hospitals it supports in Syria's Damascus governorate reported having received about 3,600 patients displaying neurotoxic symptoms on Wednesday morning. 
 
 But according to Syrian state-run television's depiction of events, government forces came into contact with a gas attack on Saturday in Jobar, on the edge of Damascus. Several of the soldiers were "suffocating" from exposure to gases as they entered the city, according to state TV. 
 
 "It is believed that the terrorists have used chemical weapons in the area," Syrian TV reported, citing an anonymous source. The government uses the term "terrorists" to describe rebel forces. 
 
 Broadcast video showed a room containing gas masks, gas canisters and other paraphernalia that could be used in a gas attack. The army said it uncovered the cache in a storage facility in the area. 
 
 CNN could not independently confirm the authenticity of video shown by the government or rebels. ||||| Syria agreed Sunday to a U.N. investigation into last week's alleged chemical weapons attack outside Damascus _ a deal a senior White House official dismissed as "too late to be credible," saying the United States has "very little doubt" President Bashar Assad's forces used such weapons. 
 
 FILE- This Aug. 21, 2013, file image provided by by Shaam News Network, which has been authenticated based on its contents and other AP reporting, purports to show several bodies being buried during a... (Associated Press) 
 
 Black columns of smoke rise from heavy shelling in the Jobar neighborhood, east of Damascus, Syria, Sunday, Aug. 25, 2013. Syria reached an agreement with the United Nations on Sunday to allow a U.N.... (Associated Press) 
 
 Black columns of smoke rise from heavy shelling in the Jobar neighborhood, east of Damascus, Syria, Sunday, Aug. 25, 2013. Syria reached an agreement with the United Nations on Sunday to allow a U.N.... (Associated Press) 
 
 Syrian Information Minister Omran al-Zoubi speaks during an interview with the Associated Press at his office, in Damascus, Syria, Sunday, Aug. 25, 2013. Al-Zoubi denied Syria has ever used chemical weapons... (Associated Press) 
 
 Syrian Information Minister Omran al-Zoubi speaks during an interview with the Associated Press at his office, in Damascus, Syria, Sunday, Aug. 25, 2013. Al-Zoubi denied Syria has ever used chemical weapons... (Associated Press) 
 
 In this photo taken on a government organized media tour, Syrian army soldiers are seen deployed in the Jobar neighborhood of Damascus, Syria, Saturday, Aug. 24, 2013. Syrian state media accused rebels... (Associated Press) 
 
 Syrians gather in the Marjeh square, in Damascus, Syria, Sunday, Aug. 25, 2013. Syria reached an agreement with the United Nations on Sunday to allow a U.N. team of experts to visit the site of alleged... (Associated Press) 
 
 The hardening of the U.S. position came as calls for military action grow. In a sign the U.S. may be a step closer to an armed response, naval forces have already been dispatched toward Syria's coastal waters, although President Barack Obama has cautioned against a hasty decision. 
 
 With France, Britain, Israel and some U.S. congressmen urging swift military action against Assad's regime if the use of chemical agents is confirmed, the U.N. team's conclusions could have a dramatic impact on the trajectory of the country's civil war. 
 
 The agreement struck in Damascus calls for U.N. experts already in the country to begin an investigation Monday into the suspected chemical attack on rebel-held areas in the capital's eastern suburbs. 
 
 Anti-government activists and Doctors Without Borders say that more than 300 people were killed in an artillery barrage by regime forces Wednesday that included the use of toxic gas. The government calls the allegations "absolutely baseless." 
 
 The suburbs hit in the suspected chemical strike, collectively known as eastern Ghouta, are under the control of rebel fighters, and regime artillery and warplanes have pounded the area for days. The U.N. inspectors will have to traverse through both government-held and opposition-controlled turf to conduct their probe. Rebels have said they will help facilitate the visit. 
 
 Under Sunday's agreement with the U.N., the Syrian government "affirmed that it will provide the necessary cooperation, including the observance of the cessation of hostilities at the locations related to the incident," U.N. spokesman Martin Nesirky said in a statement. 
 
 In Washington, a senior administration official said the U.S. has "very little doubt" that regime forces used chemical weapons in Wednesday's attack, an assessment that was "based on the reported number of victims, reported symptoms of those who were killed or injured" as well as witness accounts and facts gathered by the U.S intelligence community. 
 
 The official, who insisted on anonymity because of lack of authorization to speak publicly about the developments, was dismissive of the Syrian government's agreement to grant access to the U.N. team, saying it was "too late to be credible." 
 
 The regime's continuing shelling of the site would have "significantly corrupted" any available evidence of chemical weapons, the official said. 
 
 The U.N. team was in Syria to look into three earlier suspected chemical attacks, with a mandate to determine whether such weapons were used, not who was responsible for unleashing them. There was no indication that the mission's brief had been expanded to assess who was behind Wednesday's attack. 
 
 Even as the pressure mounts for a strong international response, there is no guarantee that foreign powers will take action if the U.N. confirms chemical agents were used. But the scale of the attack makes this instance far harder to ignore than previous suspected cases. 
 
 A senior State Department official, not authorized to comment publicly by name, said U.S. Secretary of State John Kerry spoke with the top diplomats of Britain, France, Canada and Russia as well as U.N. Secretary Ban Ki-Moon. 
 
 The official said Kerry stressed that if the Syrian regime wanted to prove to the world that it had not used chemical weapons in this incident, it would have stopped shelling the area and granted immediate access five days ago. 
 
 U.S. Defense Secretary Chuck Hagel offered no hints Sunday about likely U.S. responses, telling reporters traveling with him in Malaysia that the Obama administration was still assessing intelligence about Wednesday's attack. 
 
 "When we have more information, that answer will become clear," he said when a reporter asked whether it was a matter of when, not if, the U.S. will take military action against Syria. 
 
 "There are risks and consequences for any option that would be used or not used _ for action or inaction," he told reporters. "You have to come to the central point of what would be the objective if you are to pursue an action or not pursue an action. So all those assessments are being made." 
 
 The U.S. has about a dozen F-16 jets, a Patriot missile battery and as many as 1,000 American troops in Jordan, which all could also be used in any military action. U.S. administration and defense officials in recent days have said the most likely military move would be the launch of Tomahawk missiles off ships in the Mediterranean. 
 
 U.S. senators John McCain and Lindsey Graham, who have criticized the Obama administration's hands-off approach to Syria, said in a joint statement that in light of the latest suspected chemical attack, "now is the time for decisive actions." 
 
 "The United States must rally our friends and allies to take limited military actions in Syria that can change the balance of power on the ground and create conditions for a negotiated end to the conflict and an end to Assad's rule," the statement said. 
 
 In Paris, French President Francois Hollande said a "body of evidence" suggests that chemical weapons were used during last week's attacks, and "everything" leads France to believe that the Assad regime was behind it. 
 
 Conveying new urgency about the situation, Hollande's office said he spoke about Syria by telephone Sunday with Obama, as well as prime ministers David Cameron of Britain and Kevin Rudd of Australia. The White House said in a statement the two leaders discussed "possible responses by the international community and agreed to continue to consult closely." 
 
 Just over a year ago, Obama called the use of chemical arms in Syria a "red line" that would carry "enormous consequences." Since then, U.S. intelligence believes that such weapons have been used on a small scale several times, but that has precipitated no major shift in American policy or substantial action against the Assad regime. 
 
 So far, the U.S. has largely limited its support for the rebels to non-lethal supplies. In June, Washington said it would begin sending weapons to the rebels, although there's no indication that has happened yet. 
 
 Russia, a close ally of the Assad regime, welcomed Syria's decision to allow a U.N. probe, and said the U.S. should await the findings and realize that a unilateral use of force would be a mistake. 
 
 Foreign Ministry spokesman Alexander Lukashevich said Washington and European partners shouldn't take a "gamble" that could have "catastrophic consequences" for Syria and the region as a whole. 
 
 In Damascus, Syrian Information Minister Omran al-Zoubi said the United States was using allegations of chemical attacks as an "excuse" to intervene in Syria, accusing Washington and Europe of turning a blind eye while Saudi Arabia and Turkey _ both backers of the anti-Assad rebellion _ provide chemical weapons to foreign jihadi fighters in Syria. 
 
 "The materials are coming from Saudi Arabia and Turkey," al-Zoubi said in an interview with The Associated Press in the Syrian capital, adding that foreign fighters were carrying out chemical attacks to implicate the Syrian government in hopes of prompting international military intervention. 
 
 "Instead of the Americans searching for the source of these chemical weapons in Saudi Arabia and Turkey, they wait for them to be used to give a pretext to intervene in Syria," he said. 
 
 Iran, a close ally of the Assad regime, warned against a possible U.S. military move against Syria. The semi-official Fars news agency quoted Gen. Masoud Jazayeri as warning that "trespassing over the red line in Syria will have severe consequences for the White House." He did not elaborate. 
 
 Doctors Without Borders said that three hospitals it supports in the area of the attack reported receiving roughly 3,600 patients with "neurotoxic symptoms" over a three-hour period Wednesday. Of those, 355 died, the Paris-based group said. 
 
 That roughly coincided with the death toll given by the Britain-based Syrian Observatory for Human Rights, which tallied 322 killed. Casualty figures have varied widely over the alleged attack, from just over 300 to around 1,300 killed. 
 
 Rebels on the ground outraged by the images coming out of the Damascus suburbs have also threatened to take forceful action. 
 
 On Sunday, the head of an al-Qaida-linked Syrian rebel group vowed to target villages inhabited by members of Assad's minority Alawite sect to avenge the purported chemical weapons attack. 
 
 In an audio recording posted on a website frequently used by Islamic extremists, Jabhat al-Nusra leader, Abu Mohammed al-Golani, said: "Revenge for the blood of your children is a debt to be paid back ... 1,000 rockets will be fired at them in revenge for the massacre of Ghouta." 
 
 The authenticity of the claim could not be immediately verified. 
 
 ___ 
 
 Lucas reported from Beirut. Associated Press writers Jamey Keaten in Paris, Jamal Halaby in Amman, Jordan, and Kimberly Dozier, Lolita C. Baldor and Matthew Lee in Washington contributed to this report. ||||| Media playback is unsupported on your device Media caption The BBC's Yolande Knell: "The UN has always said the safety of its team is paramount" 
 
 Unidentified snipers have opened fire on a convoy of UN experts investigating suspected chemical weapons attacks in Syria's capital, the UN has said. 
 
 One car was shot at "multiple times", forcing the convoy to turn back. 
 
 Syrian state media blamed opposition "terrorists" for the attack, though the claim could not be verified. 
 
 The UN team later resumed its mission, entering the western district of Muadhamiya to gather evidence, before returning to central Damascus. 
 
 Hundreds died in alleged attacks on Wednesday in five districts near Damascus. 
 
 The US said there was little doubt that Syrian forces used chemical weapons in the attacks, which reportedly killed more than 300 people in rebel-held areas. 
 
 Syrian President Bashar al-Assad dismissed the accusation as "an insult to common sense" and warned the US against military intervention. 
 
 "If someone is dreaming of making Syria a puppet of the West, then this will not happen," he told the Russian newspaper Izvestiya. 
 
 'Intimidation' 
 
 The 20-member UN inspection team has been in Syria since 18 August to look into three earlier suspected chemical attacks. They were given permission on Sunday to examine the Damascus locations. 
 
 Image caption The UN inspectors have been talking to doctors in Muadhamiya 
 
 The experts intend to take soil, blood, urine and tissue samples for laboratory testing but they are unlikely to apportion blame for any of the attacks. 
 
 Video footage posted online appears to show UN inspectors in Muadhamiya taking samples and talking to residents. 
 
 They went to a Red Crescent centre and spoke to doctors, opposition activists said. 
 
 On the video, which the BBC has not been able to fully authenticate, one resident is heard telling an inspector of heavy raids on the district, with "over 600 canister strikes...12 tanks, 100 soldiers". 
 
 Shortly after setting out from their hotel in Damascus, the inspectors' cars came under fire "multiple times by unidentified snipers", according to a statement from the UN. 
 
 Analysis Whitehall officials say no firm decision is likely to be taken on how Britain will respond to last week's alleged chemical attack in Syria until at least Wednesday. That is when UK PM David Cameron will be chairing a session of the National Security Council, attended by military and intelligence chiefs and senior ministers. It follows intense consultations between London and Washington with Downing Street keen to stress the two countries are acting in concert. Any military response, if it is decided on, is most likely to be confined to a one-off or limited guided missile strikes on selected Syrian military targets using Tomahawk cruise missiles fired from US Navy warships stationed hundreds of miles away in the eastern Mediterranean. US vessels there are reported to have around 400 such missiles onboard, while a Royal Navy submarine in the region can also carry cruise missiles. But Russia, Syria and Iran have all issued strong warnings against any western military action. 
 
 The team returned safely back to the government checkpoint before setting out again. 
 
 The convoy was "deliberately targeted" and it seemed someone was trying to intimidate the team, the UN Secretary General's spokesman, Farhan Haq, told the BBC. 
 
 The inspectors have now returned to their hotel and are expected to resume their work on Tuesday. 
 
 Military action 
 
 A year ago, US President Barack Obama said the use of chemical weapons by the Syrian government would be "a red line" that could trigger US military action. 
 
 Washington has recently bolstered its naval presence in the eastern Mediterranean, and military leaders from the US, UK and their allies are meeting in Jordan. 
 
 But the UN Security Council remains divided, with China and Russia appearing unlikely to drop their objection to stricter sanctions on Mr Assad's government. 
 
 Chinese Foreign Minister Wang Yi said on Monday that diplomats should be cautious in dealing with the chemical weapons issue, and Moscow warned Western nations not to prejudge the outcome of the inspections. 
 
 Western politicians have begun to suggest taking action outside of the UN system. 
 
 UK Foreign Secretary William Hague told the BBC that action could be taken without UN approval if there was "great humanitarian need" in Syria. 
 
 His French counterpart Laurent Fabius suggested the UN Security Council could be bypassed "in certain circumstances". 
 
 Media playback is unsupported on your device Media caption William Hague: UN Security Council has not shouldered its responsibilities 
 
 But in his latest comments on the crisis, Russian Foreign Minister Sergei Lavrov said any intervention in Syria without a UN mandate would be a "grave violation of international law". 
 
 The West, he told a news conference in Moscow, had not been able to come up with any proof of chemical weapons use while "saying at the same time that the red line has been crossed and there can be no delay". 
 
 'Neurotoxic symptoms' 
 
 Western officials were unimpressed with Syria's decision to allow in the UN experts. 
 
 Mr Hague said evidence could have been tampered with, degraded or destroyed in the five days since the attack. 
 
 A senior White House official, quoted by AP news agency, dismissed the visit as "too late to be credible". 
 
 Medecins Sans Frontieres (MSF) said on Saturday that three hospitals it supports in the Damascus area had treated about 3,600 patients with "neurotoxic symptoms" on Wednesday morning, of whom 355 had died. 
 
 While MSF said it could not "scientifically confirm" the use of chemical weapons, staff at the hospitals described a large number of patients arriving in the space of less than three hours with symptoms including convulsions, pinpoint pupils and breathing problems. 
 
 Syria's security forces are widely believed to possess large undeclared stockpiles of mustard gas and sarin nerve agent. 
 
 It is one of seven countries that have not joined the 1997 convention banning chemical weapons. ||||| German politicians across the political spectrum are urging extreme caution over proposals by the US and Britain to launch a military offensive in Syria. 
 
 The governing Christian Democrats (CDU) of chancellor Angela Merkel insisted that Germany was pressing on in pursuit of a diplomatic solution, but suggested for the first time that it might support an international military response if it is proved that Syrian government troops used chemical weapons to attack its opponents. Merkel's spokesman, Steffen Seibert, said that if UN inspectors confirmed the use of chemical weapons, Syria "must be punished". 
 
 He confirmed for the first time the government's belief that there is a "very high probability of a poison gas attack" and while he would not rule out the use of force, he would not speculate on what sort of response might be appropriate. Foreign Minister Guido Westerwelle said that if the attack was confirmed, "Germany would be among those who consider consequences to be appropriate." 
 
 The statements indicate a shift away from the government's hitherto insistence on a political solution to the conflict, with defence minister Thomas de Maiziere declaring just this weekend that: "Outside military intervention in this terrible civil war in Syria is just not something I envisage," while Philipp Missfelder, head foreign policy expert of the CDU insisted: "Germany is rightly continuing to work on a political remedy." 
 
 The government's shift could yet turn the Syrian issue into a hotly debated election theme that could even influence the outcome of the poll in a month's time. 
 
 Most Germans are against military intervention and the current debate recalls the fallout in 2002 when Germany was divided over the looming intervention in Iraq ahead of that year's general election. Making the war his central election issue, and successfully presenting his party as the party of peace in opposition to the conservatives' candidate Edmund Stoiber and the CDU head Angela Merkel, the SPD's candidate Gerhard Schröder, while accused of opportunism, managed to secure his reelection. 
 
 Until now, the issue of war had not featured as an election issue at all with all parties in solid agreement – cementing their pacifist alliance in a Bundestag vote a month ago – that intervention by the west in Syria was to be avoided at all costs. The sense of solidarity is in contrast to the situation in 2011 when German politicians were divided over the UN security council's resolution over intervention in Libya. 
 
 But with the German population skeptical about military intervention and weary of its armed forces' less than triumphant experiences in Afghanistan, any party that pushes the call for western involvement, most especially anything which would involve German participation, risks losing voters. Despite widespread predictions that her reelection is a shoo-in, a decision by Merkel to support military intervention could have serious consequences for her future. 
 
 Meanwhile, Claudia Roth, the head of the opposition Greens and the strongest political voice of the pacifist movement in the Bundestag, has continued to stress the urgency of coming up with a non-military remedy. "All parties need to come to a political solution as soon as possible," she said. She stressed that China and Russia "have to put pressure on the Syrian dictator Bashar al-Assad and to stop delivering weapons to Syria immediately". 
 
 The Social Democrats' (SPD) candidate for next month's general election, Peer Steinbrück, urged "restraint regarding the discussions about military intervention". 
 
 Most politicians have welcomed the decision by Assad to allow entry to UN weapon inspectors even if only to secure more time in which a political solution might be reached. "This is an important agreement in a dramatic situation," said Westerwelle. 
 
 Dirk Niebel of the liberal Free Democrats (FDP) said that Germany should focus its energies on helping the civilian population. "There are more than 100,000 dead and two million refugees and they're the ones we need to help including here in Germany," he said.
– Syria may have given UN inspectors the OK to access the site of last week's alleged chemical weapons attack, but inspections are not off to a great start. A UN rep confirms that one of the team's vehicles was "deliberately shot at multiple times" by unidentified snipers in Damascus; all are safe. The shooting reportedly occurred in the buffer zone between rebel- and government-controlled territory, and the team will head back to the area once it replaces its vehicle, reports the AP. The Syrian government, for its part, has already blamed "terrorists," reports CNN. More: Once they finally reach the site of last week's alleged attack, UN inspectors will spend two days taking soil, blood, urine, and tissue samples, reports the BBC. But Reuters reports that the US and its allies aren't expecting much: They believe the regime's offer to allow inspectors to the site came too late and any remaining evidence has probably been destroyed by heavy shelling. To wit, a senior White House official dismissed the visit as "too late to be credible." Assad, meanwhile, says that any American attempt at military intervention will be doomed to fail. "Failure awaits the United States as in all previous wars it has unleashed, starting with Vietnam and up to the present day," he said in an interview with a Russian newspaper. UN chief Ban Ki-moon warns that "every hour counts" in determining the facts of what was a "major and terrible incident," reports the Guardian. "We cannot allow impunity in what appears to be a grave crime against humanity," he said. But the UN Security Council, which is split on the issue, has already failed to shoulder its responsibilities and the UK and its allies may have to take action without its approval, Britain's foreign minister says. "Is it possible to respond to chemical weapons without complete unity on the UN Security Council?" William Hague tells the BBC. "I would argue yes it is, otherwise it might be impossible to respond to such outrages."