Coalition forces in Iraq are continuing isolated battles with loyalists to a radical Shi'ite cleric.
Coalition troops in Iraq battled insurgents in southern Iraq.
Several Iraqis were killed and wounded during fighting in the holy city of Karbala. U.S. helicopters engaged in the battles, smashing militia positions with cannon fire.
British troops were forced to fight through three ambushes on their way from Basra to Amara, south of Baghdad. Several Iraqis were reported to have been killed. At least two Britons were wounded.
In Nassiriya, Iraqi militants fired mortars and rocket-propelled grenades at the headquarters of the coalition administration building. There were no reports of casualties among the Italian, British and American officials inside offices of the building. Coalition authorities say the situation there has since quieted down.
In the northern city of Mosul, a group of Iraqis lining up to join the new army were attacked with mortars that killed four civilians and wounded more than a dozen others.
Loyalists of wanted Iraqi Shi'ite cleric Moqtada al-Sadr have been waging intense battles against coalition forces in southern Iraq for more than a month.
Over the past few days, the 31-year-old cleric has said he would disband his Mehdi army, if asked to by Shi'ite religious leaders. But he now says he will not withdraw from Najaf, and will not disband his militia.
Dan Senor, spokesman for the Coalition Provisional Authority in Baghdad, said Saturday the cleric must meet two key demands.
"We are committed to a peaceful resolution in Najaf and surrounding areas," he said. "We want to minimize bloodshed. But, two non-negotiable points are that Mr. al-Sadr has to face justice and he has to disband and disarm his militia. We appreciate the fact that a number of Iraqi notables have stepped forward and are trying to mediate, are trying to reach a peaceful resolution here. We encourage that, but, those two points I stated earlier, that Moqtada al-Sadr must disband and disarm his militia and that he must face justice remain our two fundamental conditions."
Mr. al-Sadr is wanted for the murder last year of a rival pro-U.S. cleric.
Najaf was reported to be relatively quiet Saturday following heavy fighting there Friday.