A bomb blast at a bus terminal in a tribal region of northwest Pakistan has killed at least three dozen people, according to reports.

A remote-controlled device was detonated at the Jamrud bazaar about 15 miles west of the city of Peshawar and also wounded about 70 other people, some critically.

Jamrud is located in the famed Khyber tribal region, which also used to serve as one of the principal supply routes for NATO troops in Afghanistan before Pakistan authorities shut it down in retaliation for the U.S. accidentally killing 25 Pakistani soldiers.

It was a huge blast and caused damage to a number of vehicles at the bus terminal, Khyber tribesman Khan Zaman said, according to Reuters.

A local shopkeeper and witness to the blast said that people were burning.”

The Jamrud attack was the deadliest in Pakistan since a bomb attack killed 40 people last August in a mosque (also in Jamrud).

However, it is unclear who the target for this attack might have been and no group has yet claimed responsibility for it. The Jamrud area, close to the Afghan border, is notorious for its large number of militant groups, some which launch attacks on the Pakistani government; others which are even anti-Taliban.

M Ilyas Khan, a BBC correspondent in Islamabad, commented: “The bombing in Khyber comes amid heightened tensions between the Pakistani security forces and factions of the TTP, an anti-Pakistan umbrella organization of Taliban militants. Pakistani soldiers who were being held hostage by militants were killed in two separate incidents last week in revenge over what a TTP spokesman described as ongoing military operations against the militants.”

Khan added: “In Khyber tribal region, the military has been conducting limited operations against a number of militant groups for several years. But local tribes have also formed armed groups of volunteers to fight militants. They have often attracted retaliatory attacks from the militants, who have targeted mosques and marketplaces to hit the tribesmen. This latest attack may simply be continuing that pattern.”

There were about 120 bomb attacks in Pakistan last year, according to Agence France Presse (AFP), or about one every three days. However, despite the horrific toll these attacks have taken, there were actually more such atrocities committed in 2009, when more than 200 such incidents were recorded.