Speaking on condition of anonymity because they were not authorized to speak to the media, Pakistani officials said missiles had been fired at the vehicle from a drone near the Angore Adda, border town of South Waziristan. According to eye-witnesses the vehicle exploded into a ball of flames.

An official added that two missiles were fired at the vehicle and that two foreigners were among the dead. The term foreigner is used by Pakistani officials to refer to militants from Arab and Central Asian countries.

Washington has been intensifying its drone strikes in the region despite public opposition from Pakistan. The US argues that the strikes are necessary to hit militants involved in cross-border attacks on Western forces in Afghanistan.

The latest strike comes amid increasing tensions between Pakistan and the United States following a recent claim by top US military officer, Admiral Mike Mullen, that Pakistan's main spy agency backed militants who carried out attacks against American targets in Afghanistan. Pakistani politicians at a conference in Islamabad Thursday rejected the US allegations.

Agencies: dpa, AP / Marina Joarder
Editor: Grahame Lucas