The Syrian military says an airstrike by the US-led coalition hit a regime military position Saturday.
The US military said an airstrike may have struck Syrian soldiers, but the coalition thought it was hitting ISIS militants.
A statement from US Central Command said the coalition conferred with the Russian military before the strike.
“The coalition airstrike was halted immediately when coalition officials were informed by Russian officials that it was possible the personnel and vehicles targeted were part of the Syrian military,” CENTCOM said.
The Russian military said 62 Syrian soldiers were killed near Deir Ezzor Airport, according to the state-run Sputnik News Agency. It quoted Russian Maj. Gen. Igor Konashenkov as saying two F-16s and two A-10s carried out four strikes.
ISIS militants launched an attack on the Syrian position after the airstrikes, Sputnik reported, citing the Russian Ministry of Defense.
The London-based Syrian Observatory for Human Rights put the death toll at 83 and said at least 120 soldiers were wounded.
The incident comes during a fragile ceasefire. A ceasefire deal went into effect Monday and calls for a halt to the violence between the Syrian regime and rebel forces, but it does not cover militant groups considered terrorists, such as ISIS and Jabhat Fateh al-Sham, formerly known as al Nusra Front.
The ceasefire has offered some respite from violence in the civil war, which has killed an estimated 430,000 people since 2011 and touched off an international refugee crisis. But there have been reports of violations, and the Russians have said the United States is not fulfilling its obligations.
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