More than 100 fighters aligned with Syrian President Bashar al Assad were killed in Syria's Deir al-Zor province after U.S.-led coalition and coalition-backed local forces thwarted an allegedly large attack late Wednesday and early Thursday, a U.S. official told Reuters.
The heavy death toll underscored the large size of the attack, which the U.S. official said included about 500 opposing forces, backed by artillery, tanks, multiple-launch rocket systems and mortars. The official spoke to Reuters on condition of anonymity. teleSUR Middle East correspondent Hisham Wannous confirmed the reports.
No U.S. troops were killed or wounded in the incident, officials said. Still, some U.S. troops had been embedded at the time with Syrian Democratic Forces, SDF, whose headquarters in Syria's Deir al-Zor province had been a target of the attack. One SDF fighter was wounded in the incident, the official said.
"We suspect Syrian pro-regime forces were attempting to seize terrain SDF had liberated from Daesh in September 2017," the official said using the Arabic term for the Islamic State group.
Meanwhile it is not clear what the makeup of the pro-Syrian government forces was and whether it included Syrian army soldiers. Syrian state television confirmed the reports Thursday and said the U.S.-led attack took place east of the Euphrates river in Deir al-Zor province in eastern Syria, causing casualties. Statements carried by Syrian television stations called it a "new aggression" and "an attempt to support terrorism."
"International coalition forces are bombing popular forces fighting 'Daesh' and the SDF [Syrian Democratic Forces] east of the Euphrates river and there are reports of casualties," the statements said. A reporter for the state TV station Ikhbariya said there were "dozens of dead and wounded" as a result of the attacks.
The U.S. official claimed that the pro-Assad forces were "likely seeking to seize oil fields in Khusham that had been a major source of revenue for Daesh from 2014 to 2017."
SDF includes different ethnic militant groups from Syria and is led by the Kurdish nationalist Marxist militia YPG. The force has proved to be the most effective against the Islamic State group and has been receiving military assistance from Washington for the past few years.
Neither U.S. officials nor the U.S.-backed coalition have offered details on the attacking forces. The Syrian army is supported by Iranian-backed militias, Lebanese resistance Shitte group Hezbollah and Russian forces and contractors.
The U.S.-led coalition had alerted Russian officials about the presence of SDF forces in the area far in advance of the thwarted attack, the U.S. official said. "Coalition officials were in regular communication with Russian counterparts before, during and after the thwarted attack," the official said.