At least 31 militants were killed Saturday during airstrikes by Pakistani fighter jets in the country's restive northwest, the military said.

The attacks, which took place in the Tirrah Valley of Khyber tribal district, also destroyed four hideouts.

The military has been targeting Taliban and Lashkar-e-Islam militants in the region since October.

"Four terrorist hideouts and a suicide bomber training centre were destroyed. 31 terrorists including some suicide bombers were killed," a statement said.

The army has intensified its offensives in the tribal areas after the massacre of 150 people, 134 of them children, in a school in Peshawar in December.

Pakistan described the carnage as its own "mini 9/11" and a game-changer in the fight against extremism.

Pakistan also ended its six-year-old moratorium on the death penalty in terror cases last month in the wake of the slaughter at an army-run school in the northwestern city of Peshawar on December 16.

Seven convicted militants have been hanged so far since the de facto ban on capital punishment ended.