Islamabad  - Nearly 100 Islamic militants were killed Thursday in two separate clashes with security forces in north-west Pakistan, officials said.

Military troops, backed by gunship helicopters and artillery fire, targeted rebel positions in the Tangkhata area of Bajaur district in the country's lawless tribal region.

"Up to 90 insurgents, most of them foreign fighters, died," said a security official, who spoke on condition of anonymity.

Army spokesman Major Murad Khan said initial reports suggested that an important local commander - Qari Ziaur Rehman - and more than a dozen foreign fighters were killed.

The term foreign fighters is used to refer to al-Qaeda members of Arabic or Central Asian origin.

"The death toll could drastically rise as there were indications that the miscreants had suffered big losses," Murad told Deutsche Presse-Agentur dpa.

He said two soldiers also died in the firefight that continued for several hours.

Since last month, the military has been fighting Taliban in Bajaur district, from where the militants target US-led international forces in neighbouring Afghanistan.

About 600 militants have been killed in clashes spanning several weeks, according to official figures.

The military operation, which triggered an exodus from Bajaur to safer areas in the adjoining North-West Frontier Province, was halted on September 1 after lawmakers from the tribal belt threatened to withdraw their support to Asif Ali Zardari in the presidential elections.

It was resumed on September 6, the day Zardari won the election. (dpa)