A powerful roadside bomb targeting an anti-Taliban militia ripped through a pick-up vehicle in Pakistan's tribal belt on Thursday killing at least five people, government officials said. 

The blast badly damaged the pick-up in a remote village close to the Afghan border, in the northwestern district of Bajaur, where Pakistani troops have been fighting for years to dislodge Taliban militants.

"It was a planted IED (improvised-explosive device) which exploded when the vehicle passed. Five people have been killed and eight others were wounded," Adalat Khan, a government official in Chamarkand village, told AFP by phone.

"Three of those who died are members of an anti-Taliban militia and one is a 10-year-old boy. The fifth one is the driver."

Irshad Shah, another government official, confirmed the casualties although there were fears that the death toll could rise.

Washington considers the tribal belt a global headquarters of Al-Qaeda and the most dangerous region on earth, where Islamist militant groups are plotting attacks on American troops fighting in Afghanistan and on targets in the West.

In many areas, tribesmen have set up anti-Taliban militias, sponsored by the government, in a bid to drive militants out of their communities.

AFP