Military sources stated Sunday that at least 20 Pakistani soldiers died and more than 30 were wounded after a bomb rocked an army convoy in the northwest region of Bannu.
The explosion rocked the convoy in a town near North Waziristan, a lawless region on the Afghan border where terrorists often hide in the mountains.
The Telegraph UK reports that according to police officials, the blast took place as a convoy of army troops and paramilitary Frontier Corps left Bannu; security forces have cordoned the area off to investigate.
Intelligence officials confirmed to CNN that an improvised explosive device had been planted in an 18-seater van, killing most of the passengers inside.
So did Pakistani Taliban (the Tehrik-e-Taliban Pakistan, or TTP) spokesman Shahidullah Shahid, who claimed responsibility for the attack.
"The bombing was carried out to (avenge) the killing of Maulana Waliur Rehman, commander of TTP South Waziristan, who was killed on May 29, 2013, in a U.S. drone strike in Miranshah," Shahid stated to the news outlet.
Shahid also called Reuters, threatening more attacks.
"With the help of God we claim responsibility for this," he stated to reporters. "The army is our enemy. We will carry out many more attacks like this again."
The assault follows a threat by the Pakistani Taliban to step up attacks on security forces after the group elected a new leader, Mullah Fazlullah, at the end of last year.
CNN reports that Pakistani Interior Minister Chaudhry Nisar Ali Khan condemned Sunday's attack and has demanded an explanation as to why civilian vehicles were being used in the convoy.
Terror attacks have become more and more common with the rise of the Taliban in Pakistan. Earlier this month, a Pakistani high school student tackled a suicide bomber attempting to blow up his school in the Hangu region of the country. 15 year old Aitzaz Hasan was killed, but he saved the lives of his schoolmates in the heroic act.