A car bomb exploded this morning at a police station in a town west of Baghdad, causing about 17 deaths and 30 casualties, witnesses and the US military said.
The attack in Khaldiyah, about 50 miles west of Baghdad, occurred near the main police station, witnesses said.
US troops immediately blocked off the area, and two helicopters were seen hovering overhead.
There were no American soldiers in the area when the bomb exploded.
It was not clear whether the attack was a suicide bombing. US troops have been targeted by suicide bombers three times in the past week. Dozens of soldiers have been injured and one was killed.
Khaldiyah is located in the so-called Sunni Triangle west and north of the capital, where attacks against occupation troops and their Iraqi allies have been fiercest.