The attack came in the Mir Ali area of Miranshah, the main town in the North Waziristan tribal region, a hub for Taliban and al Qaeda linked militants on the Afghan border.Ansarul Mujahideen, a little-known militant group linked to the Tehreek Taliban Pakistan faction claimed the responsibility hours after the attack."It is revenge for the killing of Hakimullah Mehsud by a US drone ," Abu Baseer, a purported spokesperson of the group told AFP by telephone."We will continue such attacks in future as drones continue to kill our people," he said.A senior security official told AFP that "a truck laden with explosives was rammed into the checkpoint when security officials were offering evening prayers".As a result, "five soldiers embraced shahadat (martyrdom)", the official said."The checkpoint has been completely destroyed and 34 injured security personnel have also been recovered," he said, revising an earlier toll of 4 people dead and 25 injured."Security personnel are still removing bodies from the checkpoint," he added.The attack took place at Kharoji checkpoint, about three kilometres east of Miranshah.Another security official confirmed the toll, adding that out of the 34 injured, 28 were soldiers and 6 from the Frontier Corps, the paramilitary group serving in Pakistan's northwest and tribal areas."The soldiers were offering prayers at the time of the blast," the official said.The umbrella Tehreek-e-Taliban Pakistan faction and al Qaeda linked militants have led a bloody campaign against the Pakistani state in recent years, carrying out hundreds of attacks on security forces and government targets, concentrated largely in the northwest.