Security sources told Reuters that a US air base in the Al-Omar oil field in Deir Ezzor Governorate, northeastern Syria, was bombed today, Friday.

And the spokesman for the National Security Council, John Kirby, announced that the US military responded to the killing of an American contractor who killed and wounded five American soldiers in an attack by a kamikaze drone "of Iranian origin" on a base of the US-led coalition forces near Al-Hasakah in northeastern Syria.

Kirby added that the US Central Command responded by attacking facilities used by "groups affiliated with the Iranian Islamic Revolutionary Guard," which led to the killing of 11 Iranian-backed fighters and wounding six others.

The spokesman said, "The American forces are protecting their mission to support their allies in Syria," referring to the Kurdish "Qasd" forces.

US Defense Secretary Lloyd Austin said President Joe Biden ordered the strikes.

"The airstrikes are in response to today's attack, as well as a series of recent attacks against coalition forces in Syria by groups affiliated with the Iranian Revolutionary Guard," Austin said Thursday.

And US sources reported that the American strikes hit targets near Al-Mayadeen and Al-Bukamal, in eastern Syria.

It is believed that about 930 American soldiers are deployed in Syria.