Unidentified attackers shot dead two policemen on polio duty in southern Tank district on Saturday, police said.
A third policeman sustained injuries in the attack.
District health office Tank Dr Ihsanullah confirmed the attack and said that unidentified armed men opened fire on the policemen.
District Police Officer Tank Sahibzada Sajjad said that search operation was underway against the attackers.
On the other hand, banned Tehrik Taliban Pakistan claimed responsibility for the attack.
Separately, a police man and proclaimed offender were killed in a police encounter in Mardan district.
Police said that proclaimed offender Nisar resisted arrest and opened fire on a police contingent, when the cops tried to arrest him.
An official said that proclaimed offender shot dead a cop identified as Sartaj Bahadur and was also killed in police firing.