The Pakistani authorities launched an offensive in the troubled Bajur region three months ago in an attempt to disrupt the Taliban's influence over the area.

The government is also under pressure to stop the flow of fighters into neighbouring Afghanistan, whose administration is also tackling violent unrest involving anti-government forces.

Peshawar airport hit

In a separate incident, Kashif Alam, a Pakistani police official, confirmed on Wednesday that three rockets had been fired at Peshawar's airport at 1am local time [20:00 GMT].

It is the third time in one week that Peshawar airport - which is also the main air force base - has been hit by rockets.

Dost Mohammad, a police official, said the runway was slightly damaged and there were no casualties.

In addition, thousands of people across the northwest region were left without power supplies after suspected Taliban-linked fighters blew up an electricity pylon carrying a main power line supplying electricity to Peshawar and other towns.

Shaukat Afzal, a local power company spokesman, said alternative measures were being taken to restore supply.

The garrison city of Peshawar is the capital of the North West Frontier Province region of Pakistan.