Pakistani jets have bombed a militant stronghold close to the Afghan border, officials said Tuesday.

The air strikes come as the Pakistani military prepares for a ground offensive in South Waziristan province and a day after a suicide car bombing targeting Pakistani troops killed 41 people Monday, the fourth deadly militant attack in just over a week.

Tuesday's air strikes destroyed about 15 houses in the Makeen, Ladha and Barwand regions of South Waziristan, according to an intelligence official who spoke on condition of anonymity because he was not authorized to speak to the media.

The air strikes are believed to be a prelude to Pakistan's plan to launch what is expected to a long and bloody ground operation in the mountainous region of South Waziristan to clear the area of militants.

A Pakistani army spokesman declined to give a timetable for when ground operations would begin, but there has been speculation that it could be imminent.

Week of deadly attacks

Monday's suicide bombing was one of two bloody attacks over the past few days as the Taliban pledged to mobilize its forces across Pakistan.

The Taliban also claimed responsibility for an attack on the nation's heavily fortified army headquarters, claiming a cell from a Punjabi faction of the Pakistani Taliban was responsible for the attack, which led to the deaths of nine militants and 14 others.

Pakistani officials believe the attack on the military base originated not from Punjab but from South Waziristan, where they say 80 per cent of militant attacks are planned.

The Taliban claimed responsibility for two earlier attacks last week. On Friday, a suspected militant detonated an explosives-laden car in the northwestern city of Peshawar, killing 53 people, and on Monday a suicide bomber killed five UN workers at the World Food Program building in Islamabad.

With files from the Associated Press