A US soldier was killed Monday when a roadside bomb exploded under a military convoy near the flash-point Iraqi town of Fallujah, a senior coalition official said.
"One US coalition soldier was killed today" about 18 kilometre's (10 miles) north-west of Fallujah, the official said.
In another report, US troops in the northern Iraqi city of Mosul killed four people in a firefight after their patrol came under fire, a US military spokesman said on Monday.
On Sunday evening, a US military police patrol saw a vehicle similar to one that had fired on US soldiers earlier that day, the US army said in a statement.
The patrol approached the vehicle, whose passengers opened fire, the statement said. The military police then fired back, killing all four people inside. Two US soldiers were lightly wounded.
The statement said the four people might have been connected with a drive-by shooting in Mosul early on Sunday, which wounded two US military police. Soldiers found weapons inside the car, including rocket propelled grenades and a launcher.
There was a string of attacks in Mosul on Sunday, where insurgents fighting the US-led occupation have stepped up strikes on American soldiers, foreigners.
A British and a Canadian civilian, both bodyguards, were killed in a drive-by shooting and three Iraqi bodyguards were killed in a separate attack on a convoy carrying the Iraqi minister of public works.
Insurgents fired rocket propelled grenades at a US military vehicle, and two employees of the US-run Iraqi Media Network were wounded in a drive-by shooting.
A grenade attack wounded a policeman in the city centre and a rocket, apparently aimed at the city hall, hit a nearby boys school, but failed to explode.
TWO IRAQI WOMEN KILLED IN ACCIDENT: Two Iraqi women were killed, and a police officer and a child wounded Monday when a civilian car and US armoured vehicle crashed into each other on a road near Tikrit, north of Baghdad, police said.
"At 10:15 am (0715 GMT), one of the nine vehicles of a US army convoy crashed into a civilian car, killing two women, and wounding a child and the driver, who is a policeman," police Captain Ali Farhan told AFP.
Lieutenant Colonel Hussein Sallum, police spokesman in Tikrit, said a similar accident involving a US army vehicle and civilian minibus on the same road Sunday killed seven people.