A Kurdish peshmerga looks at the body of what they say is an Islamic State militant on the outskirts of Tel Ward, west of the city of Kirkuk after attacking jihadist positions around the oil-rich city . Kurdish forces drove Islamic State militants back from the oil-rich city of Kirkuk in northern Iraq on Monday, in an attack which was backed by heavy air strikes from a U.S.-led coalition. Speaking to a local TV channel near the frontline, Kirkuk governor Najmaldin Karim said the purpose of the offensive was to secure the city, which the Kurds have held since last summer. Peshmerga fighters began shelling Islamic State positions at dawn before advancing along a 20-mile front southwest of the city, seizing several villages and gaining around three miles in places. Monday's gains bring the Peshmerga closer to the ISIS stronghold of Hawijah, where black-clad militants have paraded the bodies of what they said were 20 Shi'ite militiamen they had executed. Speaking by telephone from the frontline near Tel Ward, Major-General Omar Saleh Hassan said: 'This morning we launched an attack on three axes. Our advances are continuing.' He said his forces faced little resistance from Islamic State militants who are also fighting to hold the city of Tikrit around 110 km southwest of Kirkuk, as Iraqi forces close in. Just north of Tikrit, home city of executed Sunni former president Saddam Hussein, Iraqi security forces and Shi'ite militia fighters began an offensive to regain control over the town of al-Alam. Military commanders said some of the attacking force were ferried across from the west bank of the Tigris river, while others were approaching from other directions. 'We have confirmed information from inside Al-Alam that a few Daesh (ISIS) fighters are still inside, mostly suiciders. 'This is why we attacked them from multiple directions in order not to give them time to catch their breath,' Al-Alam mayor Laith al-Jubouri said, referring to the fighters by their Arabic acronym. Jubouri, who has spent time with the attacking forces outside Al-Alam, said clashes were continuing in the south, west and north of the town. In the Kirkuk offensive, elite Kurdish counter-terrorism units were taking part and one official said they had managed to detonate four vehicles rigged with explosives by firing on them from a distance. Scroll down for video . Kurdish Peshmerga forces gather as they look at bodies whom they say are Islamic State militants . Kurdish forces drove Islamic State militants back from the oil-rich city of Kirkuk in northern Iraq on Monday in an attack which was backed by heavy air strikes from a U.S.-led coalition . The Kurds took full control of Kirkuk last August as the Iraqi army collapsed in the north and Islamic State militants overran almost a third of the country. But the city has remained vulnerable, with the frontline no more than 20 kilometres away in some places and only an irrigation canal separating the two sides. In late January, Islamic State briefly overran Kurdish defences around Kirkuk. Revenge is sweet: Kurdish Peshmerga fighters pose for a photo holding an Islamic State flag in the village of Sultan Mari west of the city of Kirkuk after they  re-took the area from the terror group . Kurdish Peshmerga forces walk past a destroyed building belonging to the Islamic State militants, on the outskirts of Tel Ward, west of the city of Kirkuk . Meanwhile, officials said the jihadist group executed 20 people who wanted to fight against them in the northern Iraqi province of Kirkuk. The killings of the men, who wanted to join anti-ISIS paramilitary forces known as Popular Mobilisation units, took place in the town of Hawijah, a police intelligence officer and two local officials said. The executions could not be independently confirmed, but a gruesome series of photos posted online and shared on social media are evidence that they took place. Kirkuk governor Najim Al-deen Omar visits the Peshmerga forces on the border city which has been recaptured from ISIS . Kirkuk has remained vulnerable to attack, with the frontline no more than 20 kilometres away in some places and only an irrigation canal separating the two sides . The photos show the bodies of more than a dozen different men strung by their feet from light poles, what appears to be a communications or electricity tower, and under a massive sign featuring the ISIS flag and name. Captions under the photos said the men were members of the Popular Mobilisation units and used a derogatory term that could either refer to the units' Shi'ite leadership, or indicate that the men were believed to be Shi'ites. ISIS spearheaded a sweeping offensive last June that overran large parts of the country north and west of Baghdad, including in Kirkuk province. Peshmerga forces take up positions in a town west of Kirkuk city after they regained the area from ISIS militants . Monday's gains bring the Peshmerga, pictured, closer to the ISIS stronghold of Hawijah, where militants have paraded bodies through the streets . Security forces backed by militia are battling to regain ground, with support from a US-led coalition and Iran. The Popular Mobilisation units -- which are dominated by Shi'ite militia but include other volunteers, including Sunnis - have played a key role in the  fight, shoring up the government's flagging troops. But Shi'ite militiamen have also been accused of carrying out atrocities targeting Sunni Arabs in areas retaken from ISIS.
Kurds launch massive offensive backed by strikes from U.S.-led coalition .
Gained swathes of land southwest of the city after seizing several villages .
Brings them near ISIS stronghold of Hawijah where jihadis killed 20 militia .
Men reportedly strung by their feet from light poles under Islamic State flag .
A Kurdish peshmerga looks at the body of what they say is an Islamic State militant on the outskirts of Tel Ward, west of the city of Kirkuk after attacking jihadist positions around the oil-rich city . Kurdish forces drove Islamic State militants back from the oil-rich city of Kirkuk in northern Iraq on Monday, in an attack which was backed by heavy air strikes from a U.S.-led coalition. Speaking to a local TV channel near the frontline, Kirkuk governor Najmaldin Karim said the purpose of the offensive was to secure the city, which the Kurds have held since last summer. Peshmerga fighters began shelling Islamic State positions at dawn before advancing along a 20-mile front southwest of the city, seizing several villages and gaining around three miles in places. Monday's gains bring the Peshmerga closer to the ISIS stronghold of Hawijah, where black-clad militants have paraded the bodies of what they said were 20 Shi'ite militiamen they had executed. Speaking by telephone from the frontline near Tel Ward, Major-General Omar Saleh Hassan said: 'This morning we launched an attack on three axes. Our advances are continuing.' He said his forces faced little resistance from Islamic State militants who are also fighting to hold the city of Tikrit around 110 km southwest of Kirkuk, as Iraqi forces close in. Just north of Tikrit, home city of executed Sunni former president Saddam Hussein, Iraqi security forces and Shi'ite militia fighters began an offensive to regain control over the town of al-Alam. Military commanders said some of the attacking force were ferried across from the west bank of the Tigris river, while others were approaching from other directions. 'We have confirmed information from inside Al-Alam that a few Daesh (ISIS) fighters are still inside, mostly suiciders. 'This is why we attacked them from multiple directions in order not to give them time to catch their breath,' Al-Alam mayor Laith al-Jubouri said, referring to the fighters by their Arabic acronym. Jubouri, who has spent time with the attacking forces outside Al-Alam, said clashes were continuing in the south, west and north of the town. In the Kirkuk offensive, elite Kurdish counter-terrorism units were taking part and one official said they had managed to detonate four vehicles rigged with explosives by firing on them from a distance. Scroll down for video . Kurdish Peshmerga forces gather as they look at bodies whom they say are Islamic State militants . Kurdish forces drove Islamic State militants back from the oil-rich city of Kirkuk in northern Iraq on Monday in an attack which was backed by heavy air strikes from a U.S.-led coalition . The Kurds took full control of Kirkuk last August as the Iraqi army collapsed in the north and Islamic State militants overran almost a third of the country. But the city has remained vulnerable, with the frontline no more than 20 kilometres away in some places and only an irrigation canal separating the two sides. In late January, Islamic State briefly overran Kurdish defences around Kirkuk. Revenge is sweet: Kurdish Peshmerga fighters pose for a photo holding an Islamic State flag in the village of Sultan Mari west of the city of Kirkuk after they re-took the area from the terror group . Kurdish Peshmerga forces walk past a destroyed building belonging to the Islamic State militants, on the outskirts of Tel Ward, west of the city of Kirkuk . Meanwhile, officials said the jihadist group executed 20 people who wanted to fight against them in the northern Iraqi province of Kirkuk. The killings of the men, who wanted to join anti-ISIS paramilitary forces known as Popular Mobilisation units, took place in the town of Hawijah, a police intelligence officer and two local officials said. The executions could not be independently confirmed, but a gruesome series of photos posted online and shared on social media are evidence that they took place. Kirkuk governor Najim Al-deen Omar visits the Peshmerga forces on the border city which has been recaptured from ISIS . Kirkuk has remained vulnerable to attack, with the frontline no more than 20 kilometres away in some places and only an irrigation canal separating the two sides . The photos show the bodies of more than a dozen different men strung by their feet from light poles, what appears to be a communications or electricity tower, and under a massive sign featuring the ISIS flag and name. Captions under the photos said the men were members of the Popular Mobilisation units and used a derogatory term that could either refer to the units' Shi'ite leadership, or indicate that the men were believed to be Shi'ites. ISIS spearheaded a sweeping offensive last June that overran large parts of the country north and west of Baghdad, including in Kirkuk province. Peshmerga forces take up positions in a town west of Kirkuk city after they regained the area from ISIS militants . Monday's gains bring the Peshmerga, pictured, closer to the ISIS stronghold of Hawijah, where militants have paraded bodies through the streets . Security forces backed by militia are battling to regain ground, with support from a US-led coalition and Iran. The Popular Mobilisation units -- which are dominated by Shi'ite militia but include other volunteers, including Sunnis - have played a key role in the  fight, shoring up the government's flagging troops. But Shi'ite militiamen have also been accused of carrying out atrocities targeting Sunni Arabs in areas retaken from ISIS.
20-mile front southwest of the city, seizing closer to the ISIS stronghold of Hawijah, where backed by heavy air strikes from a U.S.-led holding an Islamic State flag in the village of different men strung by their feet from light