The U.S. military carried out multiple airstrikes in Syria on Thursday night against Iran-aligned groups whom it blamed for a drone attack that killed an American contractor, wounded another, and also hurt five U.S. troops, the Pentagon said, Reuters reported.

Both the attack on U.S. personnel and the retaliation were disclosed by the Pentagon at the same time late on Thursday.

The attack against U.S. personnel took place at a coalition base near Hasakah in northeast Syria at approximately 1:38 p.m. (1038 GMT) on Thursday, it said.

The U.S. intelligence community assessed that the one-way attack drone was Iranian in origin, the military said.

U.S. Defense Secretary Lloyd Austin said the retaliatory strikes were carried out at the direction of President Joe Biden and targeted facilities used by groups affiliated with Iran's Islamic Revolutionary Guards Corps (IRGC).

"The air strikes were conducted in response to today's attack as well as a series of recent attacks against Coalition forces in Syria by groups affiliated with the IRGC," Austin said in a statement.

The drone attack on U.S. personnel caused wounds that, for three services members and a contractor, required medical evacuation to Iraq, where the U.S.-led coalition battling the remnants of Islamic State has medical facilities, the Pentagon said. The other two wounded American troops were treated at the base in northeast Syria, it added.