US accused of striking Syrian military base, allowing IS to advance

The Syrian military has claimed that the US-led coalition struck its base in Deir al-Zour, allowing the so-called Islamic State to advance in the area, which is fiercely contested.

The British-based Syrian Observatory for Human Rights says that at least 80 soldiers have been killed in the strikes, according to their source at the airport.

Coalition forces have said they believed they were striking an IS fighting position that they had been tracking for a "significant amount of time" prior to the strike.

They added that the strike was stopped immediately once coalition officials were informed that it was possible the personnel targeted were part of the Syrian military.

The Observatory also said that Russian jets had been bombing in the same area at the same time, and that their source said the air strikes had allowed IS to advance on the hill overlooking the air base.

The Russian foreign ministry has indicated that it wishes to convene an emergency UNSC meeting, and says the air strikes jeopardise the US-Russia peace deal.

In a statement, the Syrian military calls the incident a "serious and blatant attack on Syria and its military" and "firm proof of the US support of Daesh (IS) and other terrorist groups".