Kandahar, Afghanistan Tribal Afghan fighters withdrew artillery and heavy weapons Tuesday from the mountain stronghold of Osama bin Laden's al-Qaida network in eastern Afghanistan, signaling the worst of the fighting was over.
U.S. special forces were remaining in the area of Tora Bora, a leading tribal commander, Hazrat Ali, said. U.S. military leaders said they faced the task of searching hundreds of caves in the region for lingering al-Qaida members and for traces of bin Laden.
The search will be "tough, dirty, hard work," Defense Secretary Donald H. Rumsfeld said at a meeting of NATO defense ministers in Brussels, Belgium.
The several valleys in the Tora Bora region each have several hundred caves, some of which have been sealed by U.S. bombardment and may need reopening, Gen. Peter Pace, vice chairman of the joint chiefs of staff, told reporters in Washington.
"And so it's going to be step by step, cave by cave, and to put a time limit on that would be imprudent right now," he said.
Some Afghan and U.S. officials had placed bin Laden at Tora Bora during the fighting, but his presence there was never confirmed. Deputy Defense Secretary Paul Wolfowitz said Tuesday that the al-Qaida leader may have been killed in the bombing of the caves.
"I think it's possible he could be dead in the bottom of one of them," he said.
After resisting an assault by U.S. warplanes and tribal eastern alliance forces for days, al-Qaida fighters fled Monday, leaving behind piles of documents, passports and other evidence in the caves. A few hundred al-Qaida fighters of the estimated 1,000 to 2,000 were reported to have been killed or captured. There was no word on whether the rest had fled or initial estimates were wrong.
Ali on Tuesday declared the tribal forces' operation completed. He was quoted by the Afghan Islamic Press agency as saying there was no information that more al-Qaida fighters remained in the caves.
As his forces withdrew, a tank crawled along a dusty, narrow valley road, followed by troops in pickup trucks. Villagers came out and waved.
"Al-Qaida is finished. I am now going to go home," one soldier said.
Mohammed Aman Khiari, another tribal commander, said he doubted bin Laden was still holed up in Tora Bora because if he were his loyalists would keep fighting. "Now maybe he has gone somewhere else, or maybe he is dead," Khiari told reporters.
Pakistan deployed reinforcements on its border near Tora Bora and patrolled with helicopter gunships. But the frontier is laced with goat paths that have served for decades as routes for smuggling goods and infiltrating fighters.
In southern Afghanistan, Marines at their base in Kandahar's airport raised an American flag that had been flown near New York's ground zero and bears the names of 23 policemen killed in the Sept. 11 attack on the World Trade Center.
"They took 23 great cops. Pay back time," read one unsigned note among the many messages scrawled on the red and white stripes of the flag by relatives and colleagues of the victims.
The dead officers' names, and those of 17 sailors lost in last year's suicide bombing of the USS Cole in Yemen, were handwritten on the flag's white stars.
In other developments:
Two U.S. C-130 aircraft on a nighttime flight mistook small arms fire on the ground for a missile attack and took evasive action, U.S. officials said. They saw muzzle flashes from Afghans on the ground firing guns to celebrate the end of the Muslim holy month of Ramadan, Central Command in Tampa, Fla., said.
British Defense Secretary Geoff Hoon said his country could deploy the first troops in the Afghan capital, Kabul, for an international security force by Saturday, when the interim government under Pashtun tribal leader Hamid Karzai is due to assume office. Britain will lead the force and contribute up to 1,500 troops, Prime Minister Tony Blair told Parliament on Monday.
A second American soldier was injured while trying to clear land mines in Afghanistan.
Wolfowitz said interrogations of al-Qaida and Taliban detainees so far have not produced much reliable information about bin Laden's location.
Three Taliban or al-Qaida members being detained on the USS Peleliu in the Arabian Sea are thought to be "fairly important people," Wolfowitz said, without identifying them.
Another 15 prisoners were en route from a detention facility in northern Afghanistan to one the Marines built at their base in Kandahar airport, the Defense Department said. Also being held on the Peleliu are an American and an Australian who joined the Taliban.
The war against al-Qaida, meanwhile, was extended beyond Afghanistan's borders.
On the southern tip of the Arabian Peninsula, Yemeni special forces fired tanks and artillery Tuesday, trying to capture five suspected bin Laden supporters being protected by a tribe in the remote mountains of central Yemen, tribal and security sources said.
Tribal sources said four tribesmen were killed in the fighting around mountain villages.
Wolfowitz said he had no information on the fighting but said the administration has long been concerned about "pockets where we believe al- Qaida people have sheltered and may be there now" in Yemen, particularly along the remote Saudi border.
With the ouster of the Taliban and fighting tapering off near Afghan cities, hundreds of refugees poured into Afghanistan back from neighboring Pakistan, which houses an estimated 3 million Afghans. At the Torkham border crossing, families lugged bags of food, clothes and holiday presents through the gate.
In southern Afghanistan, a tribal intelligence officer said Taliban leader Mohammed Omar had fled to Baghran, in the foothills of the south-central mountains, with 300 to 400 fighters, but there was no immediate plan to pursue him.
"Every hour, we're getting reports of where he is," from contacts in the area, said Haji Gulalai, intelligence chief for Kandahar's governor, Gul Agha.
"America knows where he is. But we need to be in the same area to help guide any bombing," Gulalai told The Associated Press. "Without our help, America will end up bombing civilian areas. We haven't yet given the green light to the Americans to start bombing."
Baghran is a gateway to the unguarded northern frontier to Turkmenistan, a notorious smugglers' track toward the breakaway republic of Chechnya, where bin Laden's support remains strong.
Associated Press correspondents Chris Tomlinson, Geoff Spencer, Doug Mellgren and Riaz Khan contributed to this report.