The use of white phosphorus by the United States-led coalition fighting Daesh in Syria and Iraq raises serious questions about the protection of civilians, Human Rights Watch said today.
"The multipurpose munition should never be used as an incendiary weapon to attack personnel or materiel in populated areas, even when delivered from the ground," the rights group said.
It is known that US forces are using white phosphorus in both Mosul, in Iraq, and in the Daesh stronghold of Raqqa, in Syria. But the rationale for its use by US-led coalition, say the rights group, is unclear.
White phosphorus ignites when exposed to atmospheric oxygen. Its chemical reaction can create intense heat (about 815° C), light, and smoke. It is used as a weapon to start fires that burn people and objects.
"No matter how white phosphorus is used, it poses a high risk of horrific and long-lasting harm," said Steve Goose, arms director at Human Rights Watch, before instructing US-led forces to take all feasible precautions to minimise civilian harm when using white phosphorus in Iraq and Syria.
While Human Rights Watch was not able to independently verify whether the use of the munitions resulted in any civilian casualties, a Raqqa resident living in Beirut told the New York Times that an internet cafe in Raqqa was recently hit by white phosphorus, killing around 20 people.
The report cites a number of incidences where white phosphorous was used by the US coalition. A video published on Facebook on 8 June, which was covered by a number of news agencies concerning an attack in Syria, shows the use of ground-fired artillery projectiles containing white phosphorus, which are distinctive when air-burst.
The Washington Post published photographs of the deployed Marine unit equipped with white phosphorus projectiles, as well as similar pictures showing white phosphorus projectiles with US Army units outside Mosul. Footage shot in Mosul, Iraq, on 3 June also shows the use of ground-fired projectiles containing white phosphorous.
The purpose of the use of white phosphorus is unclear. According to a US-led coalition comment to the media, the purpose of the use of white phosphorous was to "suppress and obscure ISIS [Daesh] snipers so that the civilians could reach friendly forces."
Human Rights Watch confirmed that the US-led coalition states that as a matter of policy it cannot publicly discuss the use of specific munitions, but admits to using white phosphorus in its operation in Iraq and Syria.
Deploying white phosphorous using air-delivered incendiary weapons in civilian areas is prohibited under Protocol III of the Convention on Conventional Weapons (CCW).