Rebel fighters in Syria are developing their own hand-made weapons as they battle the government regime. Fighters from the Suqour al-Sham Brigade are setting up weapons factories in caves to make shells and rockets as they take on the might of President Bashar Al-Assad's regime. These pictures show men developing mortar shells from gas canisters and making their own rockets using welding materials. Shell: A man works on a mortar shell inside a cave used as a weapon factory operated by rebel fighters from Suqour al-Sham Brigade . Basic: The men use basic welding tools to prepare their mortar shells and other weaponry . Welder: The Suqour al-Sham Brigade are understood to have approximately 400 fighters in their ranks . The Suqour al-Sham Brigade were established in 2011 and are believed to be a mix of military defectors and civilian volunteers . They are understood to have approximately 400 fighters in their ranks, and are aligned with the Free Syria Army. The brigade are based in the Idlib Province in north-west Syria, which has come under sustained attack from the government's forces during the long-running civil war. Last week, Syrian activists and the Western-backed opposition accused the government of carrying out a devastating chlorine gas attack against a rebel-held town in Idlib that killed at least six people and left dozens, including children, choking and gasping for breath. The reported use of poison gas on the town of Sarmin was the first alleged chemical attack since the U.N. Security Council approved a  resolution  that condemns the use of toxic chemicals such as chlorine in Syria. But a Syrian military official in Damascus denied any government role in the attack and blamed it on rebels, adding: 'The army did not and will never use any internationally-prohibited weapon.' Prepared: The rebels are seen here preparing a range of devices to fire at President Bashar Al-Assad's . Simple: Gas canisters are converted into basic shells and loaded to be fired by mortars . Fighters: The Suqour al-Sham Brigade  are believed to be a mix of military defectors and civilian volunteers . Bombs: A man inspects gas canister devices that have been prepared to fired against government forces . Secure: The rebel fighters have built their weapons factories deep inside caves in the Idlib Province . Yesterday, two car bombs killed at least 25 people and wounded another 80 celebrating the new year festival of Nowruz in the mainly Kurdish city of Hassaka in northeastern Syria, according to state media. The Syrian Observatory for Human Rights group, which tracks the four-year-old Syrian civil war, said 33 people, including children, were killed in the attack which it said was carried out by Islamic State.
Suqour al-Sham Brigade manufacture their own weapons in caves . Rebel fighters have set up  factories to fight government regime . Pictures show men preparing shells and mortars in basic conditions . More than 200,000 estimated dead in last four years of civil war .