The Syrian military has used air-delivered incendiary bombs in at least four locations across Syria since mid-November 2012 according to interviews with witnesses and video analysis. Human Rights Watch is also investigating unconfirmed reports of the use of such weapons in other parts of Syria. Human Rights Watch has identified the weapons as ZAB-series incendiary aircraft bombs that release submunitions containing the flammable substance thermite. Incendiary weapons are designed to set fire to objects or to cause burn injuries. A total of 106 nations have prohibited the use of air-delivered incendiary weapons in populated areas, but Syria has not banned the weapons.