A US military strike in Syria on Thursday was "government terrorism" and caused a massacre, Syrian government negotiator Bashar al-Ja'afari said on Friday, while Russia called it an unacceptable breach of Syrian sovereignty.
US officials told Reuters that the US military carried out the airstrike on Thursday against militia supported by the Syrian government that posed a threat to US forces and US-backed Syrian fighters in the country's south.
Ja'afari said he had raised the incident with UN mediator Staffan de Mistura at peace talks in Geneva.
"We discussed the massacre that the US aggressor committed yesterday in our country. This subject was widely discussed," Ja'afari told reporters.
"The important thing is that our political ambition is higher because we want to focus on fighting terrorism represented by armed groups and the state and government terrorism happening against our country.
"This includes the American aggression, French aggression, and British aggression, whether on civilian or military targets."
The US strike was the second deliberate military attack on forces loyal to Syrian President Bashar Assad. In April, US President Donald Trump ordered cruise-missile strikes in retaliation for a chemical-weapons attack that Washington blamed on Damascus.
Russian Deputy Foreign Minister Gennady Gatilov said the US action would hamper efforts to find a political solution to the conflict.
"It is utterly unacceptable and a violation of Syria's sovereignty," Russian news agencies quoted him as saying.
"Any military action leading to an escalation of the situation in Syria has an impact on the political process."
A military source on the Syrian government side said the airstrike had hit "one of our military points," without elaborating, Syrian state TV reported.
The strike killed several people and caused material damage, the source said, saying this hampered efforts by the Syrian army and its allies to fight the Islamic State.
Gatilov complained about what he said was a separate strike that had occurred Wednesday.
"Literally a day before this (Thursday's strike) a strike was carried out which resulted in a large number of civilian deaths, which is also unacceptable," Gatilov was cited as saying.
The US has not spoken about any strikes carried out by the US-led coalition on that date.
SEE ALSO: The US just struck an Assad-supported militia in Syria after it rushed US-backed forces
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