Four bodies were retrieved from the debris on Friday while two persons succumbed to their injuries in hospital, officials in Hangu said. At least 10 policemen were among the dead. Over 50 people were injured in the deadly attack carried out by the Pakistani Taliban to avenge the killing of Osama bin Laden in a United States raid on May 2.
The bomber detonated his explosives near several government offices and a court complex in the heart of Hangu city of Khyber-Pakhtunkhwa province.
Deputy Inspector General of police Masood Afridi said an estimated 450 kilos of explosives was used in the attack.
The powerful blast destroyed 30 shops and several government buildings, including the office of the district administration chief, a police station and the district courts. Relief operations at the site of the attack continued for the second day on Friday.
Tehrik-e-Taliban Pakistan spokesman Ahsanullah Ahsan accepted responsibility for the attack in phone calls to reporters. He warned the Taliban would soon carry out "bigger attacks" as revenge for bin Laden's killing.
Cities across Pakistan have witnessed a string of deadly attacks in the wake of bin Laden's death.