The northern city of Mosul fell into U.S. and Kurdish hands Friday after an entire corps of the Iraqi army disappeared. The city quickly descended into anarchy, with looting, arson and shootings, and U.S. Special Forces were sent in to restore order.

"Why are you late? Why are you late?" people shouted at the convoy of Special Forces -- up to 40 trucks and other vehicles, along with hundreds of Kurdish fighters.

Although U.S. officials at Central Command said the Iraqis had surrendered, Lt. Col. Robert Waltemeyer -- commander of a Special Forces unit -- said there were no troops to surrender.

"We offered capitulation, but ... the Iraqi army evaporated, so there has been no formal capitulation or cease-fire," Waltemeyer told a news conference at an airbase in Mosul. "They may have just melted into the population."

Waltemeyer was the officer most immediately involved in the fighting at Mosul, and would have signed off for the coalition forces on any surrender.

With the Iraqis fighters gone, people whose allegiances were unclear started driving though the city, waving guns and shooting out car windows.

Townspeople plundered the central bank, grabbing wads of money and throwing bills in the air. Mosul University's library, with its rare manuscripts, was also sacked, despite appeals blared from the mosque minarets to the people to stop destroying their city, the Arab TV network Al-Jazeera reported.

At Saddam General Hospital, three of the five ambulances were stolen. Armed men, described as Kurds, tried to enter the hospital, but the staff managed to hold them off. Doctors' cars were stolen at gunpoint. Jumhuriya Hospital said all eight of its ambulances were taken at gunpoint.

"There is absolutely no security. The medical staff is scared for their safety. The city has fallen into anarchy," said Saddam General staff physician Dr. Darfar Ibrahim Hasan.

Trails of black smoke rose from different parts of Mosul's low-slung skyline. A state bank -- the Rashid Bank -- was on fire, along with the government printing office and several Baath Party offices.

Mosul is about two-thirds Arab. Kurds are the largest ethnic minority, and the city also includes ethnic Turks.

Earlier, Central Command spokesman Capt. Frank Thorp -- at a briefing in Qatar -- reported the 5th Corps of the Iraqi army in and around Mosul had agreed to lay down their arms. That was later contradicted by Waltemeyer.

Thorp would not elaborate on the size of the U.S. presence in Mosul, Iraq's third-largest city, with a population of more than 600,000. He also said he did not know how large the 5th Corps was.

Just a day earlier, the key northern oil city of Kirkuk also fell with barely a fight. U.S. commanders said Iraqi forces might be planning a last stand in Saddam Hussein's birthplace of Tikrit, the last major population center still in Iraqi hands. Coalition warplanes have been pounding Iraqi forces around Tikrit.

As the Iraqis abandoned Mosul, U.S.-backed Kurdish forces reached the outskirts of the city and set up checkpoints leding into the town center.

Abu Dhabi TV showed pictures of the looting of the Central Bank branch. Bills littered the street. One person had what appeared to be stacks of bound packages of Iraqi dinars stuffed under his T-shirt.

Gunmen, apparently Kurdish fighters, arrived at the bank and started swinging their rifles and firing into the air to force looters to leave.

"What is happening shouldn't happen," said one man. "This is barbaric. This is not Saddam's money. This is the nation's and the people's money."

On the square in front of the Government House, people set fire to a picture of Saddam. One man walked out of the abandoned building with a filing cabinet.

At the University of Mosul's science department, people carried off lab kits, and the computer department was cleaned out down to the wall plugs.

Teachers at the university were saddened by the looting.

Faiza Mohammed Ahmed said the looters were sent by the Americans. "It is impossible that our city that is full of morals and principles who do something like this. They are groups who came from outside Mosul," he said. "I want to get my voice to Bush: Is this liberation?"

In the city center, a woman in a chador was seen carrying a 6-foot bookcase stolen from a high school, and her teenage daughter was trailing behind, lugging a mini-bar refrigerator. And furniture was carried out from the large Mosul Hotel.

As the northern cities fell into coalition hands, thousands of young Iraqi soldiers abandoned their positions and walked south toward Baghdad on Friday, making their way home on a blacktop highway in the strong sun. The unarmed men, some of them barefoot, wore civilian clothes and carried little or nothing; some said it might take seven days to reach their hometowns.

In Kirkuk, Kurdish fighters roamed unchallenged through the streets of the city of 100,000, looters emptied government buildings down to the bathroom fixtures and statues of Saddam lay broken in the dust.

The capture of Kirkuk left Iraq's No. 2 oil region almost fully intact. Coalition leaders had feared retreating Iraqi forces might set the fields ablaze, but only one well fire raged near Kirkuk.

The United States had asked Kurdish forces not to enter Kirkuk for fear of alarming Turkey. But when the Kurds went in anyway, U.S. special operations forces were sent in to accompany them and were soon joined by elements of the Army's 173rd Airborne Brigade, which parachuted into northern Iraq weks ago, the Pentagon said.

The Turks fear that Iraq's Kurds will set up an independent state and fire up separatist sentiment among Kurds living in Turkey.

Secretary of State Colin Powell said he promised Turkey the Kurds would pull out and be replaced by U.S. troops.

Jalal Talabani, leader of one of the factions whose forces entered the city, told Turkish television that all Kurdish fighters would leave by the end of Friday.

Turkish Foreign Minister Abdullah Gul said his country has U.S. approval to send military observers to Kirkuk to make sure the Kurdish fighters keep their word.