A splinter group of the Pakistani Taliban, Tehreek-e-Taliban Pakistan Jamaat-ur-Ahrar (TTP-JA), claimed responsibility for the blast in Payee Khan, a village in Mohmand Agency that is part of the lawless Federally Administered Tribal Areas (FATA) bordering Afghanistan.
The group said it was a revenge attack, accusing tribesmen in the area of launching an assault on its forces and of capturing militants and handing them over to the government.
Security in Pakistan has improved in recent years - the military says "terrorist incidents" dropped from 128 in 2013 to 74 last year - but Islamist extremists continue to stage major attacks.
Reuters
