A suicide car bombing targeting Pakistani troops killed 41 people Monday, the fourth grisly militant attack in just over a week, as the Taliban pledged to mobilize fighters across the country for more strikes.

The Taliban also claimed responsibility for the 22-hour weekend attack on the nation's heavily fortified army headquarters, saying a cell from Pakistan's most populous province carried out the raid.

The claim that a Punjabi faction of the Pakistani Taliban was behind that strike is a sign the insurgents have forged links with militants outside their main strongholds in Pashtun areas close to the Afghan border, increasing their potency.

The army, however, maintained it was launched from South Waziristan — where the military is preparing for what will likely be a long and bloody offensive against the major base of the Taliban along the frontier.

In advance of that offensive, the militants have launched a wave of attacks across the country.

In the latest strike, a suicide bomber detonated a car packed with explosives near an army vehicle in a market in the northwest Shangla district, provincial Information Minister Mian Iftikhar Hussain said. The attack killed 41, including six security officers, and wounded 45 other people, he said.

The recent string of bloody attacks began last week when a suicide bomber blew himself up inside a heavily guarded U.N. aid agency in the heart of the capital, Islamabad, killing five staffers.

On Friday, a suspected militant detonated an explosives-laden car in the middle of a busy market in the northwestern city of Peshawar, killing 53 people.

Those attacks were followed by the raid on army headquarters in the city of Rawalpindi on Saturday that killed nine militants and 14 others.