PESHAWAR: An overnight roadside blast killed four suspected militants riding a vehicle in the northwestern Khyber tribal region on the Afghan border, security officials said.

Khyber is home to Taliban insurgents and militants from the extremist group Lashkar-i-Islam, led by local warlord Mangal Bagh.

Washington has branded the tribal belt a global headquarters of al Qaeda and wants Pakistan to do more to fight insurgents streaming across its border into Afghanistan.