The military's statement didn't specify whether any of those killed were Taliban members or say whether the ambush was linked to Tuesday's deadly attack by the group on a school in Peshawar, the capital of Khyber Pakhtunkhwa.

The military claimed that the fleeing insurgents "left behind bodies of their accomplices" after the firefight. Three members of the Pakistani security forces were wounded, it said.

CNN wasn't able to independently confirm what took place.

Pakistani security forces also killed eight militants in the southwestern province of Balochistan, including a Taliban commander, during a heavy exchange of fire, an intelligence officer said.

The military actions follow this week's horrifying Taliban attack on an army school in Peshawar that killed 145 people, 132 of them children.

The Pakistani Taliban, known as the Tehreek-e-Taliban Pakistan, said they targeted a school that mostly admits soldiers' children because the students aspired to follow in their fathers' footsteps and target militants.

They also said it was revenge for the killing of hundreds of innocent tribesmen and their children during a recent offensive by Pakistan's military.

The Pakistani army has been conducting a ground offensive aimed at clearing out Taliban and other militants in the loosely governed tribal areas of northwestern Pakistan. The campaign has displaced tens of thousands of people.

The Pakistani Taliban, which has close ties with its namesake in Afghanistan, has long taken credit for an extensive list of assaults on civilians and security forces in Pakistan.

CNN's Sophia Saifi reported from Islamabad, and Jethro Mullen reported and wrote from Hong Kong. Journalist Syed Ali Shah contributed to this report.