The Pentagon said the US military carried out several air strikes on Thursday evening in Syria targeting groups allied with Iran, which the United States accuses of carrying out a drone attack that killed an American contractor and wounded 5 American soldiers.
It said the strikes were in response to an attack on a U.S.-led coalition base near Hasaka in northeastern Syria at around 1:38 p.m. (10:38 GMT) on Thursday.
The military said U.S. intelligence assessments indicated the drone was of Iranian origin.
The statement quoted US Defense Secretary Lloyd Austin as saying, "I authorized US Central Command forces to conduct precision air strikes tonight in eastern Syria against facilities used by groups affiliated with the Iranian Revolutionary Guards."
The air strikes were in response to Thursday's attack and a series of recent attacks against coalition forces in Syria by groups affiliated with the Revolutionary Guards, he said.
In August, US President Joe Biden ordered similar retaliatory strikes in Syria's oil-rich Deir Ezzor province after drones targeted a coalition position without causing any casualties.
Hundreds of U.S. troops are deployed in Syria as part of a coalition fighting Islamic State remnants, often targeted by attacks by armed groups affiliated with or loyal to Iran.