Authorities are investigating an attack involving multiple rockets on a U.S. base in Syria, a spokesman confirmed via Twitter on Monday.
The rockets landed at approximately 7:44 p.m. local time, according to Operation Inherent Resolve spokesman Col. Wayne Marotto. U.S. forces returned fire with counter-battery artillery, he wrote.
“There are no injuries and damage is being assessed,” Marotto wrote.
Photos posted by an NBC news analyst show smoke trails from rockets that hit the Al-Omar Oil Field base in eastern Syria. Roughly 900 American troops are deployed to Syria for ongoing missions against the Islamic State group.
The attack comes less than 24 hours after the U.S. launched airstrikes on facilities used by Iran-backed militias on the Iraq-Syria border.
“The targets were selected because these facilities are utilized by Iran-backed militias that are engaged in unmanned aerial vehicle (UAV) attacks against U.S. personnel and facilities in Iraq,” Pentagon spokesman John Kirby said in a statement on Sunday.
At least five UAV attacks led to the decision to retaliate, a Pentagon spokeswoman told Military Times on Monday.
“The strikes were necessary, appropriate, and deliberate action designed to limit the risk of escalation,” Cmdr. Jessica McNulty said. “Through these and other means, we seek to make clear to Iran and Iran-backed militia groups that there will be serious consequences if they continue to attack, or to arm, fund, and train militia groups that attack our people.”
A full assessment of the damage and casualties from the strike is not complete, McNulty said. The Associated Press reported Sunday that four militia members were killed.
“The president has been clear that there will be serious consequences if Iranian leaders continue to arm, fund and train militia groups to attack our people,” White House spokeswoman Jen Psaki told reporters on Monday.
Leo Shane contributed to this report.
Meghann Myers is the Pentagon bureau chief at Military Times. She covers operations, policy, personnel, leadership and other issues affecting service members.