Separate attacks in central Iraq have killed four U.S. soldiers.
The deadly attacks all took place near the flashpoint town of Ba'qubah, about 50 kilometers north of Baghdad.
One U.S. soldier was killed and another wounded Friday when a roadside bomb exploded near their convoy. Other American troops opened fire on their attackers, and the military says they killed two of them.
In a separate incident Friday, a spokesman for the 4th Infantry Division says a soldier was trying to defuse another bomb, when it exploded and killed him.
Insurgents fired mortars at a U.S. military camp near Ba'qubah on Thursday, killing two more soldiers. The town is in the so-called Sunni Triangle, where resistance attacks have been most frequent.
A wave of rocket and mortar attacks struck Baghdad on Thursday, and U.S. forces have pounded targets in the capital for three straight nights with artillery and air support. A series of blasts also could be heard Friday from downtown Baghdad, but explosions have become so frequent that residents can rarely tell which side they come from.