Iraqi opposition in the northern city of Mosul disappeared without a fight, leaving deposed president Saddam Hussein's ancestral home of Tikrit as the only major population center left with the potential for organized resistance to U.S. forces.

As in other cities in which Hussein's government disintegrated, Mosul devolved into looting and lawlessness. Similar mob scenes played out in Baghdad, Kirkuk and Basra. In Baghdad, U.S. troops sought to restore order, imposing a dusk-to-dawn curfew in the capital. But reducing pockets of armed resistance and protecting their own forces remained the priorities for U.S. troops.

Defense Secretary Donald H. Rumsfeld said that U.S. forces are moving aggressively to arrest looters at hospitals, provide medical care and distribute humanitarian aid. Retired Lt. Gen. Jay Garner, who heads the U.S. Office for Reconstruction and Humanitarian Assistance and is assigned to impose a new civil administration in Iraq, predicted the disorder will soon be calmed.

FINDING FORMER RULERS

The Central Command said U.S. troops in Iraq would be issued a deck of 55 cards, each bearing the name and photo of a senior figure from Hussein's family, the government, the Baath Party and the Revolutionary Command Council, in the hope the toppled Iraqi leaders can be tracked down. "There are jokers in this deck," Brig. Gen. Vincent Brooks said, and Saddam is the ace of spades.

As U.S. troops began an intensified effort to find Hussein and the Iraqi leadership, the mystery of their whereabouts grew more perplexing. Many thought top officials would flee to Tikrit. But pictures taken by unmanned drones seemed to show loyalists abandoning their posts there, not preparing to make a last-ditch stand.

That left an escape to Syria as the most likely scenario for Hussein and his top advisers. U.S. military commanders stepped up reconnaissance and unmanned surveillance flights along the Iraqi-Syrian border and moved more troops to the area.

IN THE NORTH

Kirkuk, northern Iraq's other major city, fell Thursday and was immediately occupied by Kurdish guerrilla forces, who opened the way for the type of looting that occurred in other cities. The Kurds remain in control of Kirkuk despite U.S. pledges to Turkey that they would leave. Turkey fears stirring up any desires for independence among its sizable Kurdish population. But Turkey's refusal to allow the United States to open a northern front meant only a small number of U.S. troops were on the ground to act against Iraqi forces and constrain Kurdish militias.

Mosul, despite a sizable Kurdish population, was at first left alone by those militias. But one of them, the Kurdistan Democratic Party, sent forces to Mosul late yesterday to restore order, according to one of the group's senior leaders. U.S. bombers continue to attack positions in Tikrit, apparently disrupting what U.S. officials had felt might be plans for a bloody, final battle by elements of Hussein's government.

TO THE SOUTH

Fearing suicide bombings, Marines at a Baghdad checkpoint opened fire on an approaching car, killing three adults and wounding a 5-year-old girl. In a similar shooting, Marines at a checkpoint at Nasiriyah, about 200 miles south of the capital, killed two young children when they opened fire on a car whose driver failed to heed orders to halt.

Looting continued in Basra, but British troops killed five men trying to rob a bank and said that looting subsided after that.

-- James L. Rowe Jr.

Lance Cpl. Charles Berg smells a rose from Baghdad College gardens.