Suspected militants shot dead two policemen and blew up a checkpost killing five more in an attack in the central Pakistani town of Mianwali on Saturday, police said.
"Seven of our men have died in the attack that appears to be part of terrorist activity being carried out by militants across the country," Malik Tasaddaq Hayat, a senior police official in Minawali district, told Reuters.
Attacks on security forces by militants linked to al Qaeda and the Taliban have become commonplace in Pakistan in the last two years, but incidents in Mianwali have been rare.
Mianwali lies on the eastern bank of the Indus River dividing the central province of Punjab from North West Frontier Province and the tribal lands, where militancy has become rife.
There are concerns in the West and among regional neighbours that Pakistan's year-old civilian government is struggling to handle the mounting insecurity in nuclear-armed country.
On Friday, security forces unleashed helicopter gunships on militants near the Khyber tribal region, killing 52.
Militants in Khyber have been attacking truck convoys carrying supplies to Western forces in Afghanistan for the past few months, forcing the United States to step up its search for alternative routes.
On Thursday, a bomb killed 27 people outside a Shi'ite Muslim mosque in the town of Dera Ghazi Khan, and authorities suspect Sunni Muslim militants, with links to al Qaeda, were behind sectarian attacks aimed at destabilising the state.