KABUL, Afghanistan - Fighting between NATO forces and insurgents has erupted in the Afghan mountains of Tora Bora, best known as the rugged labyrinth where Osama bin Laden evaded U.S. capture nine years ago.

The Western military and Afghan officials said Wednesday that the district of Pachir Agam, in Afghanistan's eastern province of Nangarhar near the Pakistan border, had become a staging ground for Taliban and other fighters preparing attacks on NATO and Afghan troops.

At least five Taliban fighters, including two men identified as local commanders, were killed in a NATO air strike Tuesday night or Wednesday morning, officials said.

The raid was part of a campaign to dislodge insurgents from the area. NATO said no civilians were present.

The provincial police chief, Alishah Paktiawal, said the two slain Taliban commanders, identified as Shir Zaman and Zhir Gull, oversaw "terrorist operations" in the district.

The NATO force said in a statement that the group was believed to be coordinating the actions of suicide bombers and possibly planning an attack on an Afghan border post. It said a cache of weapons that included assault rifles and rocket-propelled grenades was recovered after the strike.

Together with Afghanistan's south, the country's east has been a focal point of a U.S. military buildup in recent months.

A number of extremist groups are known to operate in the area, including the Taliban, the Haqqani network, and fighters affiliated with al-Qaeda. All find shelter in Pakistan between strikes at the NATO force, officials have said.

Bin Laden's escape from a Western and Afghan manhunt in December 2001 still rankles U.S. officials, who believe it would have changed the course of what has become a long and draining conflict. This has been the deadliest year of the war, with nearly 500 American troops killed.

Tora Bora has long been synonymous with missed opportunities; last year, a report by the Senate Foreign Relations Committee asserted that the al-Qaeda chieftain could have been captured with a better-coordinated assault on the cave-riddled mountain redoubt.

Paktiawal, the provincial police chief, said that Western and Afghan military operations were continuing in the district of Chapar Har, adjacent to Pachir Agam.

A separate raid Tuesday night resulted in the breakup of a 20-member ring responsible for setting roadside mines and the arrests of two other commanders from Pachir Agam, he said.