Three US soldiers have been killed in a roadside bomb south of the Iraqi capital, Baghdad, the military says.
A blast hit their vehicle in a convoy at about 1145 (0745 GMT) in Babil province, the army said in a statement.
In other violence, the US army said it had killed three people who fired on troops as they were arresting suspected insurgents in the city of Samarra.
The Americans said the three people arrested were suspected of planting roadside bombs.
An Iraqi was wounded during the gun battle, but there were no US casualties, the military said.
Friday's attack in Babil province raised to at least 2,414 the number of US troops killed since the US-led invasion in March 2003, according to a count by the Associated Press news agency.
The names of the latest victims were withheld and the army gave no other details about the attack.