A suicide car bomber targeted a security vehicle in Pakistan's northwestern Hangu city on Thursday, killing at least six persons, including four policemen, and injuring 30 others.
The attacker, who was in an explosives-laden pick-up truck, blew himself up as a police van passed by, officials said.
Four policemen, who were in the van, were killed, district administration chief Adil Siddiq told the media.
Other officials said two civilians were also killed. Several women and children were among the injured.
Siddiq described the condition of three of the injured as serious. All the injured had been rushed to a nearby state-run hospital after the blast.
The blast, in which police officials said 600 kg of explosives were used, also hit several nearby vehicles and 15 houses.
No group claimed responsibility for the attack.
The blast came a day after a woman was killed and three others injured near Doaba town in Hangu district when an explosive device planted along the road went off as the van they were travelling in passed by.
