KABUL, Afghanistan - American bombers pummeled Kandahar, the Taliban's last stronghold yesterday, to open the way for tribal fighters preparing to storm the nearby airport as U.S. Marines patrolled the surrounding deserts.

Refugees who fled Kandahar for neighboring Pakistan said attacks by U.S.

B-52 bombers and other warplanes were heavy and relentless.

Fighters from Pashtun tribes were waiting out the heavy wave of bombardment before resuming an assault on the airport.

"We're not in any rush," said Mohammed Anwar, an ally of Gul Agha, the former governor of Kandahar whose fighters held positions on a strategic road between the city and Spinboldak, another Taliban outpost targeted by airstrikes.

Anti-Taliban forces claimed U.S. bombing raids had mistakenly destroyed one of

their headquarters in Afghanistan's mountainous east early yesterday, killing at

least eight people. There was no immediate comment from U.S. officials.

In the north, 82 Taliban fighters who had been holed up in part of a prison fortress near Mazar-e-Sharif emerged Saturday and surrendered, days after they took part in a bloody uprising against their northern alliance captors in which hundreds were killed, including a CIA agent.

Alliance soldiers forced the holdouts from their basement hiding place by pumping water in, said Dr. Arif Salimi, head of the local health office. "The soldiers poured water into the basement and it was very cold so they all came out. They couldn't take it any longer," he said.

More than 1,000 U.S. Marines are stationed at a desert base about 70 miles

southwest of Kandahar. A spokesman for the U.S. Marine task force said the patrols had had no direct encounters with Taliban troops.

Another spokesman, Capt. Stewart Upton, confirmed that a small number of liaison officers from Britain, Germany and Australia were also at the base.

Maj. James "Beau" Higgins, an intelligence officer for Task Force 58,

which combines the 15th and 26th Marine Expeditionary Units with air and naval support, said the Taliban were facing "a lot of pressure, a kind of snake closing in on them."

As well as hitting positions around Kandahar in Afghanistan's south, airstrikes pounded sites near Jalalabad. U.S. officials say both locations are possible hiding spots for prime terrorist suspect Osama bin Laden and members of his al-Qaida network.

In the Afghan capital, Kabul, the northern alliance's foreign minister, Abdullah, told reporters he believed bin Laden was hiding in one of three provinces around Kandahar - Uruzgan, Zabul or Helmand.

There were new claims that bombs, meant for the Taliban, had wrongly fallen on an area held by anti-Taliban forces in the east. Local officials said U.S. warplanes made two bombing raids and destroyed a building used by anti-Taliban forces in the town of Agom, 15 miles south of Jalalabad.

Anti-Taliban fighters and administrators had been staying in the building, said Mohammed Zeman, the anti-Taliban defense chief for Nangarhar province.

Earlier, there were conflicting accounts about U.S. bombs hitting villages late Friday and Saturday in the same region.

Villagers said 150 to 250 civilians were killed and dozens of homes were flattened. Afghan provincial officials also said U.S. planes struck the villages, although they put the death toll around 20.

An American spokesman in Washington said U.S. planes attacked a nearby military target, but denied any bombs hit the villages.

"There's lots of bombardment. Lots more than before," said Zaeed Ahmed, 32, who made it to the Pakistani border town, Chaman, yesterday.

Others said Taliban forces, as well as an undetermined number of Arab and other foreign Muslim fighters loyal to bin Laden, were moving from place to place around Kandahar to avoid air strikes.

"The Arabs want to fight to the death," said one man who identified himself only as Aminullah.

Reports of fighting around Kandahar could not be independently verified because the Taliban have refused to allow Western reporters into their territory.

The Afghan Islamic Press, a Pakistan-based news agency, reported that at least 13 civilians were killed by bombing on Kandahar on Saturday. It also said 30 people were killed in a separate attack, when their vehicles were hit by warplanes on the Kandahar-Spinboldak road.