Seven people were killed and 21 wounded in a suicide car bomb attack in the northwestern Pakistani city of Kohat on Sunday.
The city police chief says the bomber exploded his vehicle near a police station.
He says such accidents are a reaction to the government military operation in the tribal areas.
Another senior police officer said about 200 kilograms of explosives were used in the attack.
It came just a day after two suicide bombers dressed in burqas struck a crowd of displaced people collecting aid handouts, killing at least 41 and wounding more than 60 at a nearby camp.
The Kacha Pukha camp on the outskirts of the garrison city of Kohat is a registration centre for people fleeing Taliban violence and Pakistani army operations close to the Afghan border.