He said that the identity of the militants was not immediately known, adding it was also not clear whether any high-value target was present in the area at the time of the strike. An intelligence official in the area also confirmed the strike and casualties. "The latest death toll is four now," he said.
Residents said that the compound belonged to a local tribesman named Rasta Barkhan who had links with Taliban militants. A local resident on condition of anonymity told AFP that five drone aircraft made very low-altitude flights before the missile strike.
Officials say the attack took place in the stronghold of Hafiz Gul Bahadur, a militant who fought with the Taliban when US-led troops invaded Afghanistan. Bahadur is reputed to control up to 2,000 fighters whom he sends across the border but who do not attack in Pakistan.
The United States does not confirm drone attacks, but its military is the only force that deploys combat drones in the region. It was the sixth missile strike by an unmanned US spy plane so far this year, as the administration of US President Barack Obama puts Pakistan at the heart of its fight against al Qaeda and Islamist extremists.