Death toll from attack at police HQ in Pakistan rises to 31

The death toll from an explosion and gun attack at a police headquarters in northern Pakistan rose to at least 31, including 16 police personnel, a senior police official told AFP on Saturday, with fighting ongoing.

Attackers stormed the Old Police Lines complex at Kohat, a town of around 220,000 people in Pakistan's Khyber Pakhtunkhwa (KP) province, on Friday afternoon.

The police compound serves as a district-level police headquarters, housing key offices of the Counter Terrorism Department (CTD), Special Branch and several other police units.

"At least 31 people, including 16 police personnel, have been killed and more than 100 injured so far in the militant attack and suicide bombing," the official said.

"Several militants are still holed up in the Special Branch section of the Kohat Police Complex," the police official told AFP on condition of anonymity.

"An exchange of fire with them has been ongoing since late last night. Their exact number remains unclear," the official added.

A statement from the Kohat district health officer late on Friday said that more than 100 people had been injured, the vast majority of them police personnel, and several were in a critical condition.

Local militant group Ittehad-ul-Mujahideen Pakistan, a faction linked to Tehreek-e-Taliban Pakistan (TTP) -- the Pakistani Taliban -- has claimed responsibility for the attack.

AFP images showed military personnel standing by piles of bricks, rubble and blown-out walls following the attack, with soldiers carrying assault rifles guarding the complex.

Several ambulances were seen lining a street near the police compound.

Pakistan has blamed the increase in attacks in KP and the southern border province of Balochistan on militancy emanating from Afghanistan, where the Taliban government denies Afghan involvement.

The accusations have sparked a bitter rift and armed conflict between the neighbouring countries, and Pakistan has carried out deadly airstrikes it says target militants on Afghan soil.

The Taliban government in Kabul and the United Nations said dozens of civilians were killed in the latest Pakistani strikes on eastern Afghanistan in June.

Pakistan's Prime Minister Shehbaz Sharif condemned the attack on Friday evening, expressing "deep sorrow and regret over the injury of several people as a result of the blast".

He directed the "best medical assistance be provided to the injured" and called for a report into the attack.

President Asif Ali Zardari expressed "regret" over the casualties, sending his "best wishes for the speedy recovery of those injured in the blast".

"The complete elimination of Fitna-al-Khawarij and terrorists operating with foreign backing is essential for national security," he said, using another term for the TTP group.