Several rockets slammed into an Iraqi military complex that hosts U.S. forces next to Baghdad International Airport on Monday, wounding six Iraqi troops, the military said.
Security forces found launchers with rockets that had not been fired properly, indicating a larger attack was planned, a military statement said.
It is the latest in an uptick in rocket attacks targeting either Iraqi bases where American troops are located or the U.S. embassy in Baghdad.
U.S. defense officials have blamed several on Iran-backed factions in Iraq.
Security sources told AFP that the wounded in Monday’s attack belong to Iraq’s Counter-Terrorism Service, an elite unit that was created and trained by U.S. forces.
Two of them are in critical condition, the sources said.
The military complex also hosts a small group of U.S. soldiers and American diplomats.
There have been at least nine attacks against U.S. targets in Iraq in the span of six weeks. There have been no claims of responsibility and no U.S. forces have been wounded.
Security sources have linked at least one last week to Kataib Hezbollah, a powerful Shiite faction close to Iran and blacklisted by Washington.
Iran holds vast sway in Iraq, especially among the more hardline elements of the Hashd al-Shaabi, or Popular Mobilization Units, a security force largely made up of Shiite militias.
A U.S. defense official told AFP the rocket attacks made the Hashd a bigger security threat to American troops in Iraq than Islamic State.
On Friday the United States imposed sanctions on three senior Hashd figures.
Tensions between Iran and the U.S. have soared since Washington pulled out of the landmark Joint Comprehensive Plan of Action nuclear agreement with Tehran last year and reimposed crippling sanctions.
Baghdad, which is close to both countries and whose many security forces have been trained by either the U.S. or Iran, is worried about being caught in the middle.
With reporting from AFP