Security forces repulsed an attack Sunday by 600 fighters in northwestern Pakistan, most of whom had crossed the border from Afghanistan, leaving at least 40 militants dead and scores of others wounded, a military official said.

Six security forces were also killed and seven wounded in the pre-dawn attack in Mohmand agency, which lies along the volatile Afghan border.

Insurgents attacked the Pakistani Frontier Corps' Mohammad Ghat camp at about 2 a.m. with mortars and rockets, then used small arms to fire on a checkpoint near the camp, said a military official speaking on condition of anonymity because he was not permitted to comment to the media.

The bulk of the militants had earlier crossed over from Afghanistan and later joined with Pakistani allies, the official said. At least 40 militants were killed, he said.

The attackers were eventually driven off, but scattered skirmishes continued, he said.

The lawless and remote mountain region is believed to be used by pro-Taliban militants as a launching pad for attacks into Afghanistan, and is difficult for reporters to access.

Pakistan has deployed tens of thousands of troops to police its tribal regions, but Western and Afghan officials say that has not deterred militants. A major military offensive against militants in Bajur to the north has spilled over into Mohmand.

Militants frequently target tribe members in the area whom they suspect of backing government peace efforts.

Also Sunday, purported Taliban militants abducted five members of an anti-militant tribal committee in Bajur and sliced an ear off each, said local government official Israr Khan.

One of the victims told police at a hospital that their abductors warned they would slash off their other ears and their tongues if they maintained their anti-militant activities, Khan said.

Saleem Khan, a relative of one of the victims, told The Associated Press that the men had merely been manning a local guard post.

"They did not commit any crime, but the way they were "punished" is horrible and inhuman. This is very disturbing," he said.

Further south in the South Waziristan tribal agency, suspected militants abducted a government official Sunday, according to intelligence officials who requested anonymity because they were not authorized to speak with the media.

Gunmen in four vehicles stopped a convoy in which Amir Latif, a political deputy in the regional government, had been traveling, the officials said. The suspected militants bundled Latif in one of the vehicles and drove off.

Also Sunday, tribesmen were blocking the southwestern supply route for NATO forces in Afghanistan at Chaman with burning tires and felled trees. They were protesting the killing of one of their members in a raid by Pakistan's anti-narcotics force.

Police official Karam Khan said trucks were held up well ahead of the blocked points and no damage or injuries had been reported.

Most NATO supplies travel through the famed Khyber Pass, although a smaller number get to Afghanistan by a second land crossing at Chaman.