Iraqi authorities are decrying U.S. air strikes that they say killed at least three Iraqi army soldiers, two policemen, and a civilian worker, as a breach of their sovereignty.
American aircraft hit a number of positions overnight into Friday, said to be storage facilities used by a powerful militia supported by Iran.
It was done without Baghdad's approval, though, and Iraq's military says that some of the sites housed both militia fighters as well regular Iraqi soldiers and police units.
The air strikes were targeting Kataib Hezbollah, which Washington says is responsible for many attacks on U.S. led-forces.
Most recently the massive rocket attack on Wednesday that killed two American soldiers and a British soldier at an Iraqi base, although no group has claimed responsbility.
This was American general Kenneth McKenzie on Friday:
(SOUNDBITE) (English) U.S. MARINE GENERAL KENNETH MCKENZIE, SAYING:
"We believe that the collateral damage is going to be very low. We expect there are going to be fatalities on the objective but I don't have those numbers for you right now. We'll work to get those out here in the in the in the future, in the near future, as we as we continue."
This was the third time in recent months the U.S. has targeted Kataib Hezbollah, most notably the air strike at Baghdad airport that killed Iran's Major General Qassem Soleimani in January.
He was the second most powerful man in Iran at the time.
Iraq's president says continued breaches of their sovereignty undermine the government and risk turning Iraq into a failed state.