There has been fierce fighting between US troops and gunmen in the Iraqi city of Ramadi.
The largely Sunni city, to the west of Baghdad, has been a hub of pro-Saddam sentiment.
There were no immediate reports of casualties but some of the fighting was captured in dramatic video footage.
The violence came two days after former Iraqi dictator Saddam Hussein was sentenced to death by a court in Baghdad after being convicted of murder.
Meanwhile, the US military said this month's casualties included two lieutenant colonels, among the highest ranking soldiers to die in Iraq since the 2003 invasion.Lt Col Eric J Kruger, 40, was killed last Thursday by a roadside bomb along with Lt Col Paul J Finken, 40, and Staff Sgt Joseph A Gage, 28. All three men were riding in the same Humvee in eastern Baghdad.