More than 60 Syrian government soldiers were killed and dozens of others injured Saturday in US-led coalition air strikes on an air base in the east of the war-torn country, the Russian army said.
"Warplanes from the international anti-jihadist coalition carried out four air strikes today against Syrian forces surrounded by the Islamic State group in the Deir Ezzor air base," the army said in a statement.
"Sixty-two Syrian soldiers were killed and a hundred others were injured in these strikes."
The Russian military said two F-16 and two A-10 jets flew into Syrian air space from neighbouring Iraq to carry out the strikes.
"Straight after the coalition's strikes, IS militants launched an offensive," said the statement, adding that "fierce fighting against the terrorists" ensued nearby.
"If these strikes were due to an error in the target coordinates, that would be a direct consequence of the US' refusal to coordinate with Russia its fight against the terrorist groups in Syria," it said.
While Russian jets deployed in Syria were not operating in the area at the time of the coalition strikes, they later intervened "in support of the Syrian army by targeting IS", Russian General Vladimir Savchenko said.
"A total of 10 strikes were carried out" starting from 1600 GMT, he said in a television briefing.