Islamic militants ambushed a large convoy of military vehicles in troubled northwestern Pakistan on Thursday, kidnapping more than 100 soldiers after seizing their weapons, officials said.

The soldiers were traveling in 16 trucks and providing security for trucks carrying food between Wana, the main town in South Waziristan and Ladha, another town in the region, two intelligence officials said on condition of anonymity because of agency policy.

One of the officials said nearly 100 soldiers were kidnapped, while the other said there were between 100 and 120 soldiers taken. There was no indication if there was a battle or if anyone was wounded in the incident, they said.

"We confirm that several military vehicles were ambushed, and scores of our soldiers are missing, but we have no further details," said an army official based near the capital, Islamabad, who spoke on condition of anonymity because of the sensitive nature of the issue.

The reports could not be independently confirmed because the region is remote and dangerous.

A senior intelligence official in South Waziristan said about 100 soldiers were leaving Wana by road when hundreds of militants attacked them.

"Efforts are under way to trace and rescue the missing soldiers," he said.

The hostage-taking comes two days after militants freed 18 soldiers and a Pakistani government official who were kidnapped in the same region earlier this month.

Pakistan is a key ally of the U.S. and has deployed 90,000 troops to the region along the Afghan border, where American officials believe there has been a resurgence in Al Qaeda and Taliban militants.

The kidnappings come as President Gen. Pervez Musharraf faces increasing pressure from Washington to do more to secure its borders from insurgents crossing into Afghanistan to launch attacks against Afghan and international troops.