Islamabad - Two missiles fired from a suspected US pilotless aircraft on Thursday killed four militants in Pakistan's tribal region bordering Afghanistan, an official and residents said.

The missiles targeted a vehicle carrying several Islamist insurgents at around 11:15am (0600 GMT) in Kari Kot area of South Waziristan tribal district, a known sanctuary for al-Qaeda and Taliban fighters.

"Four militants died and three received serious injuries," said a security official, who spoke on condition of anonymity. "According to the information we have received from the locals, all those killed were al-Qaeda militants of Turkmen origin," he said.

A resident, Noorullah, said two US drones were seen flying overhead before the huge explosion. "The Taliban rushed to the site of the attack and have so far pulled three injured out of the vehicle that was completely destroyed by the strike," he said.

US forces have carried out several drone attacks on suspected hideouts of Taliban and al-Qaeda militants launching cross-border attacks on international forces in Afghanistan in recent months.

Though the strikes have eliminated several al-Qaeda operatives, the Pakistani government has condemned them, saying they violate its sovereignty. (dpa)