The death toll in a pair of car bombings in northwestern Pakistan rose to 27 Sunday, police and hospital authorities said.

Rescuers found two more bodies of policemen as they clawed through the rubble of a police station in the volatile Bannu district, where a suicide bomber blew up an explosives-laden pickup truck Saturday morning.

'The confirmed casualty count as of Sunday stands at 14 - nine policemen and five civilians,' police officer Talha Khan said.

Most of the victims died inside the building of Mandan police station, which was flattened by the huge explosion that left a three-metres deep crater and damaged several nearby houses and shops.

Qari Hussain, a senior Taliban leader known for training suicide bombers, claimed responsibility for the assault by telephoning different media organisations from an undisclosed location.

Separately, police said Sunday that 13 people died in the car bombing that hit a busy commercial centre in Peshawar, capital of the North West Frontier Province, just hours after the Bannu blast.

At least 125 people, including security personnel, were injured in the two separate strikes. Some were in critical condition, raising fears that the death toll could increase.

Officials claimed the recent surge of attacks in the northwestern region was a desperate reaction to the military's gains against the militants whose 'back has been broken'.

The military is battling remnants of Islamist rebels in the former tourism valley of Swat and its adjoining districts, as anti-Taliban operations have also been launched in the restive tribal region known to provide Al Qaeda and Taliban sanctuaries.

There was a lull in militant attacks on government and civilian targets after the death of Pakistani Taliban chief Baitullah Mehsud, by a US missile strike in the South Waziristan tribal district near the Afghan border, in early August.

But Hussain told the Dawn newspaper that 'the government has a misperception about Taliban after the death of Baitullah and thinks we (Taliban) have weakened'.

The Taliban chose Hakimullah Mehsud, a close aide of Baitullah, to be their new commander, amid some reports about sharp disagreement among the rebel groups.