DERA ISMAIL KHAN, Pakistani — Pakistani police say militants that struck a police convoy with a bomb attack have killed three officers in the country's northwest.

Police official Mohammad Khan says Friday's attack was aimed at the newly appointed district police chief, Zahid Ullah, who escaped unhurt.

Mohammad Khurasani, a spokesman for the Pakistani Taliban, claimed responsibility for the attack and warned of more in the future.

Dera Ismail Khan is a central town in the country's northeast and a gateway to the North and South Waziristan tribal regions, which have were a base for local Taliban until recently when the army in series of operations killed or captured militants.

Violence, however, has persisted in the town.