Syria conflict: Government helicopters 'drop chlorine' on Aleppo Syrian government forces have been accused of dropping barrel bombs containing chlorine from helicopters on a suburb of Aleppo, injuring 80 people. Volunteer emergency workers say people suffered breathing difficulties after an attack on the Sukari area. The reports could not be independently verified. A UN-led investigation last month found the government had used chlorine on at least two occasions. The Syrian government has always denied using chemical weapons. BBC