An attack by an unmanned aerial surveillance system on Saturday targeted Iraq's Ain al-Asad air base in western Iraq which hosts U.S. and other international forces, but it caused no injuries, a coalition spokesman said.
U.S. Army Colonel Wayne Marotto, spokesman for the U.S.-led coalition, said on Twitter that the attack was being investigated but that an initial report suggests that the attack took place at 0220 local time and caused damage to a hangar.
The United States accuses Iran-backed militia groups of launching regular rocket attacks against its troops in Iraq. There was no immediate claim of responsibility for Saturday's attack.