Pakistani fighter jets on Thursday pounded hideouts of the militants in the Khyber tribal region and killed 37 of them, military sources said.

The sources said that 18 other militants were injured in the strikes at the mountainous Tirah valley close to the Afghan border.

Several hideouts of the militants were also destroyed in the bombing started early morning.

Military sources had earlier stated that those who were targeted had been behind a deadly bomb attack in the Islamabad's fruit market which had killed dozens of people. The suspects had also been involved in a series of bomb attacks in the northwestern districts of Peshawar and Charsadda.

Security sources said the airstrikes were carried out to hit the banned Tehreek-i-Taliban Pakistan and the outlawed Lahskar-i- Islam. Both groups are blamed for attacks on the security forces and pro-government tribesmen in Khyber agency, a main supply route for NATO troops in Afghanistan.

The two groups have not commented on the airstrikes.

The bombing came at a time when the Taliban have refused to extend their 40-day temporary ceasefire.