Multiple Katyusha rockets were fired near Baghdad International Airport (BGW), two Iraqi military officials said early on Tuesday. There were no reports of injuries or material damage, a US defence official said.
"All military personnel are accounted for and military forces were not targeted as had been reported," the US defence official told Reuters, speaking on condition of anonymity.
The incident was a reminder of the soaring tensions in the Middle East, as speculation swirled about whether Iran and Iran-backed groups would make good on threats to retaliate after a series of Israeli major blows against Lebanon's Iran-backed Hezbollah.
Two Iraqi security sources said an initial investigation showed three rockets were fired, including one that landed near buildings used by Iraqi counter-terrorism forces, causing damages and fire to some vehicles but no casualties.
The sources had previously said at least two Katyusha rockets were also fired at a military base hosting US forces and that air defenses intercepted the rockets.
But the US official said Washington was aware of reports of an attack instead on the Baghdad Diplomatic Support Complex, which is a Department of State facility.
A US Department of State is assessing the damage caused by the attack, according to a spokesperson, who said there were no casualties.
Iraq, a rare regional partner of both the US and Iran, hosts 2,500 US troops and also has Iran-backed armed factions linked to its security forces.
Iran-aligned armed groups in Iraq have repeatedly attacked US troops in the Middle East since the Gaza war began.