A barrel bomb is an improvised unguided bomb, sometimes described as a flying IED (improvised explosive device). They are typically made from a large barrel-shaped metal container that has been filled with high explosives, possibly shrapnel, oil or chemicals as well, and then dropped from a helicopter or aeroplane.[1] Due to the large amount of explosives (up to 1,000 kilograms (2,200 lb)), their poor accuracy, and indiscriminate use in populated civilian areas (including refugee camps), the resulting detonations have been devastating.[2][3][4] Critics have characterised them as weapons of terror and illegal under international conventions.[5]
The earliest known use of barrel bombs in their current form was by the Israeli military in 1948. The second known use of barrel bombs was by the US military in Vietnam in the late 1960s. Starting in the 1990s, they were also used in Sri Lanka, Croatia and Sudan. Barrel bombs have been used extensively by the Syrian Air Force during the Syrian civil war—bringing the weapon to widespread global attention—and later by the Iraqi forces during the Anbar campaign. Experts believe they will continue to be embraced by unstable nations fighting insurgencies since they are cheap to make and utilise the advantages of a government's airpower.[6]
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