Iraq's Ain al-Asad air base, which hosts US and other international forces, was attacked with a rocket on Monday, but no one was hurt, a coalition spokesman said.
US Army Colonel Wayne Marotto, spokesman for the US-led international military coalition, tweeted that initial reports suggested the attack took place at 1:35 p.m. (1035 GMT). He said the damage was being assessed.
The United States accuses Iranian-backed militia groups of launching regular rocket attacks against its troops in Iraq. There was no immediate claim of responsibility for Monday's attack.