Police said in a statement that the bombing happened when police officers ordered a vehicle to halt for routine checking. But instead of stopping, its driver detonated explosives hidden inside. A female passenger in the car also was killed, police said.
TV footage showed a burning car as police officers cordoned off the area.
No one claimed responsibility for the bombing. But Pakistani Taliban have stepped up attacks on security forces since November, when they unilaterally ended a monthslong cease-fire with Pakistan’s government.
The violence comes days after several Pakistani Taliban detainees overpowered their guards at a counterterrorism center in northwestern Pakistan on Sunday after snatching police weapons and taking three officers hostage.
On Tuesday, Pakistan’s special forces raided the detention center, triggering an intense shootout in which the military later said 25 detainees linked to the Pakistani Taliban were killed in Bannu, a district in the Khyber Pakhtunkhwa province and part of a former tribal region.
Three troops and at least three hostages were also killed in that incident.