Coalition forces worked to restore calm in Iraq's cities Tuesday as leaders of the country's fractious factions gathered to chart their nation's future. Wary of lingering threats posed by foreign fighters, U.S. troops intensified the search for weapons of mass destruction and prisoners of war.

U.S.-picked representatives of some of Iraq's often-quarrelsome factions met in the ancient city of Ur, said to be the birthplace of biblical Abraham. The participants included Kurds, Sunni and Shiite Muslims from inside the country as well as others who have spent many years in exile. Thousands of Shiites whose representatives were boycotting the meeting staged street protests in nearby Nasiriyah.

Anger also rose in Tikrit on Tuesday as Marines tightened their hold over Saddam Hussein's hometown. Tanks barred people from crossing over a Tigris River bridge that was heavily damaged in an airstrike, and many helicopters flew overhead.

Looters ransacked a government agriculture building, but there did not appear to be the sort of widespread lawlessness seen in other fallen cities. Infuriated residents complained to a reporter that the bridge into town had been blocked for days; many said they were hungry and sick, but U.S. forces would not let them go to a hospital across the river.

''The Iraqi people want to go to their own parts of their territory -- their own lands,'' one man yelled. ''But the Americans are not letting them!''

A Marine in a passing convoy shouted, ''We're trying to bring order.'' Later, Marine Cpl. Courtney Davis, collecting automatic weapons at a checkpoint, said he'd heard from his superiors that there were still some pockets of resistance.

With fighting on the wane in much of Iraq, U.S. defense officials said Monday they soon would recall two of five aircraft carrier battlegroups stationed in the Persian Gulf. ''I would anticipate that the major combat engagements are over,'' Maj. Gen. Stanley McChrystal said at the Pentagon. ''I think we will move into a phase where it is smaller, albeit sharp fights.''

Early Tuesday, Marines searched rooms in the hotel, which serves as headquarters for many international journalists in Baghdad. They apparently detained four Iraqi men who didn't have proper identification.