Iraqi security forces attempted to seize control of the Camp Ashraf enclave in Diyala province, home to Iranian dissidents with the People's Mujahedin of Iran.
Statements by members of the PMOI blame Iraqi Prime Minister Nouri al-Maliki for the assault on the Ashraf residents. The PMOI claims several hundred residents were severely wounded, with at least 12 people dead.
Iraqi government spokesman Ali al-Dabbagh countered the claims, saying recently the activity near the camp was "a well-coordinated operation to stabilize the security situation inside the camp."
Ian Kelly, the spokesman for the U.S. State Department, said Washington was aware of the situation and had assurances from Baghdad that any action taken against Camp Ashraf residents would be humane.
"We've received written assurances from the government of Iraq that they would treat these individuals humanely and wouldn't relocate them to a country where they may suffer persecution," he said.
Iraqi forces took charge of security matters from U.S. military forces following a June deadline that required combat forces to leave Iraqi cities.
Kelly said any action on the part of the Iraqi government in relation to the residents of Camp Ashraf "is entirely consistent with their rights as a sovereign country to establish control over the area."