At least four members of Iraq's military were wounded in a rocket attack on an air base north of Baghdad, which houses US soldiers, Iraqi security officials said.
The Balad air base was targeted by six rockets and wounded an Iraqi air force officer and three enlisted men, according to the officials.
The base is located some 50 miles north of Baghdad.
A statement from the Iraqi army's official media office confirmed the attack but said eight rockets hit the base, and two officers had been wounded.
"There are American experts, trainers and advisers at the base," a defense official said, who requested anonymity because he was not authorised to speak to media.
No group has claimed responsibility for the attack.
Sunday's attack came just days after Iran fired ballistic missiles at two bases in Iraq that houses US forces, but caused no casualties.
The strike on Ain al-Asad and Irbil was in retaliation to the US killing of Iran's top general Qassem Soleimani.
Both countries appear to have stepped back from escalating tensions, which had threatened to turn Iraq into a proxy battlefield.
- Mobile phone footage shows the moment the blasts hit the US air base:
But thousands of Iranian protesters took to the streets of Tehran after leaders admitted to "unintentionally" shooting down a Ukrainian passenger plane, killing 176 people on board.
The country's government had previously repeatedly denied Western accusations they were responsible however, in the face of mounting evidence it acknowledged it had it shot down the jetliner by accident.
The plane was on route Kyiv when it was shot down last Wednesday, shortly after Iran fired the ballistic missiles at two US bases in Iraq.
The majority of people on board the plane were Iranians and Canadians.
Videos posted online showed protesters shouting anti-government slogans and moving through rail stations and pavements in Tehran, despite a police call not to demonstrate.