Islamabad: At least six people including a policeman were killed and 56 injured in a suicide bombing Tuesday in a Pakistani tribal area near the Afghan border, officials said.

The attack, claimed by banned Tehreek-e-Taliban Pakistan (TTP) in an email sent to media representatives, took place at Jamrud in Khyber Agency tribal region of north-western Khyber Pakhtunkhwa province.

The casualties were shifted to Hayatabad Medical Complex hospital in Peshawar, capital of the province long plagued by militancy.

Political Agent Shahab Ali Shah, quoted by a news website, said that the suicide bomber apparently wanted to enter his office but failed due to security measures and blew himself at the entrance gate.

Militants lurking in Khyber Agency, one of Pakistan’s seven semi-autonomous tribal districts, have been frequently targeted in air strikes amid the ongoing anti-terrorism military operation in the tribal territory.

The main focus of the military offensive has been North Waziristan tribal region where more than 3,000 militants have been reportedly killed since start of the operation in June 2014.

Last month the army launched what the military described as last phase of the operation to wipe out militant hideouts in the Shawal valley of North Waziristan.

The Shawal push followed a series of air strikes that, according to the military, killed around 200 suspected terrorists.

TTP and allied militants have carried attacks including suicide bombings from time to time in apparent retaliation to the military operations.

The top TTP leader Mullah Fazlullah is believed to be living somewhere across the border in Afghanistan along with other fugitives.