Two US soldiers were killed and five wounded in a car bomb attack against their convoy in the northern city of Mosul on Wednesday, the military said.
The car bomb was followed by small arms fire, killing two soldiers and wounding five others, two of whom immediately returned to duty, it said in a statement.
The attack took place at about 2.20 pm (1120 GMT) on the north-eastern side of Mosul.
Mosul has witnessed several car
bomb attacks against US forces
Mosul has been the site of regular car bomb attacks over the past few weeks against US forces and their allies in Iraq.
In Baghdad a third US soldier was killed in a bomb attack on Wednesday.
ِA statement released by the military said an "improvised explosive device" detonated at approximately 4.50am, killing one Task Force Baghdad soldier in western Baghdad.
Earlier on Wednesday, two Iraqi civilians died after a mortar landed on a house near a regional government building in the city of Ramadi.
US troops sealed off streets and
searched buildings in Ramadi
The deaths came as US troops moved into the town, sealing off streets and searching buildings.
Aljazeera has learned two Iraqi policemen were also killed in the al-Malab neighbourhood in eastern Ramadi after US snipers fired on them as they attended to a wounded fighter.
Just hours earlier, an Iraqi police officer was shot dead in a city north of Baghdad when unknown assailants opened fire on his car as he drove to work.
A Diyala province police official confirmed that Captain Hasan al-Bayati was ambushed about 6km east of Baquba on the main highway.
A series of mortars were also fired at an oil refinery in Iraq's second city early on Wednesday, missing the facility but wounding three Iraqi National Guard members, officials said.
In Baghdad, Iraqi interim Prime Minister Iyad Allawi on Wednesday demanded that Falluja turn over al-Qaida linked Abu Musab al-Zarqawi or face a military invasion.
"We have asked Falluja residents to turn over al-Zarqawi and his group"
interim prime minister
"We have asked Falluja residents to turn over al-Zarqawi and his group. If they don't do it, we are ready for major operations in Falluja," Allawi told Iraq's 100-member interim parliament.
The Iraqi government and leaders from Falluja have been in negotiations for weeks but talks have stalled over the status of Arab fighters who have made the town their base.