US soldiers have come under increasing attack
United States troops have come under renewed attack in the central Iraqi town of Falluja.
Rocket-propelled grenades (RPGs) were fired at US soldiers guarding a power plant late on Thursday, an American military spokesman told the AFP news agency.
Falluja, about 50 kilometres (30 miles) west of Baghdad, has been the scene of repeated attacks on US forces since clashes with the local population in April in which the Americans killed at least 15 people.
The incident came hours after another attack south of Baghdad, in which one US soldier was killed and two others were injured.
In Falluja, residents told the Associated Press news agency that insurgents had blown up a power transformer in the attack.
However a US military spokesman said they had missed their target.
Falluja residents are also quoted as saying the Americans fired back indiscriminately and hit houses and cars.
No casualties have been reported.
US troops have come under increasing attack from supporters of former Iraqi strongman Saddam Hussein.
On Thursday, assailants fired on a military ambulance south of Baghdad, killing one American - the third American soldier to be killed in Iraq so far this week.
The guerrilla-style attacks have come as US forces have launched house-to-house searches for weapons and arrested hundreds
of suspected supporters of Saddam Hussein across Iraq.