By Christopher Torchia, Associated Press, 12/23/01

TORKHAM, Pakistan -- In a huge manhunt for a handful of Osama bin Laden loyalists, Pakistani troops patrol in trucks and helicopters and train machine guns on ravines and barren hills along the border with Afghanistan.

Thousands of soldiers are searching for five al-Qaida fighters who remain at large after dozens of Arab war prisoners overpowered their Pakistani guards last week. At least 16 people, including 10 prisoners and six guards, were killed.

After intense U.S. bombing and a ridge-by-ridge assault, anti-Taliban forces in Afghanistan declared victory over bin Laden's Arab fighters, who were hiding out in the cave network at Tora Bora. But many stragglers are still believed to be on the run, and U.S. forces are helping to clear caves one by one.

Despite the downfall of the Taliban and the rout at an al-Qaida stronghold that had been considered virtually impregnable, the escape by Arab prisoners who had fled across the border from Tora Bora has put Pakistan on edge.

Some 4,000 troops were already stationed along a roughly 50-mile stretch opposite Afghanistan's White Mountains, where Tora Bora is located. Another 6,000 were brought in to search for the fugitives, who are believed to have a few Kalashnikov rifles, little ammunition and no food.

Pakistan's military dragnet is a massive undertaking that shows how hard it is to effectively police a border where refugees, smugglers and -- in centuries past -- invaders have found easy ways to cross.

Part of the region, the mountainous Tirah valley, is difficult for the army to work in because independent-minded Afridi tribesmen prefer to administer their own affairs through traditional tribal councils.

Long involved in smuggling electronics and other goods from Afghanistan into Pakistan, they found a new market when the United States began bombing the Taliban on Oct. 7.

Thousands of Afghans fled across the border to escape the bombing, and the Afridi charged $20 a head to guide them. The smuggling racket created tension with Pakistan, which shut its borders to stop the refugee influx.

Afridi tribesmen decided to cooperate with the army this time, fearing American warplanes might bomb their territory in the hunt for al-Qaida stragglers. They also got medical help from military doctors, and promises of government funds for development.

The area lies east of where the al-Qaida fighters escaped, but it is laced with mountain passes from Afghanistan that are hard to monitor, let alone seal, as Pakistan claims it has done.

Tirah lies southwest of Torkham, a border post on the historic Khyber Pass, a winding trail flanked by rocky cliffs and mud-walled tribal compounds.

On foot and horseback, the armies of Alexander the Great and Genghis Khan once passed through here; now trucks laden with goods sway along the road that links Pakistan and Afghanistan.

Cmdr. Khalil, the Afghan border chief at Torkham, said as many as 2,000 refugees had poured daily back into Afghanistan since last week, the end the end of Ramadan, Islam's holy month.

He insisted that Arab fighters would be unable to cross into Pakistan near his post -- a fugitive would likely choose a more desolate spot.

In southern Afghanistan, anti-Taliban tribal chiefs accused Pakistan of allowing top Taliban leaders to slip over the border and lie low in Chaman, Quetta and other towns. Pakistan, a former ally of the Taliban, denied the allegations.