MIRANSHAH (AFP) A US missile strike on Saturday killed at least four suspected militants in a lawless tribal belt, Pakistani security and intelligence officials said. The missile struck a compound in Ismail Khel village, 40km west of Miranshah, the main town in North Waziristan tribal region on the Afghan border. A US drone fired two missiles, which hit a compound used by militants as a training centre, a senior security official told AFP. He said the identity of the militants was not immediately known, adding that 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 the compound belonged to a local tribesman named Rasta Barkhan who had links with the Taliban. 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. 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. Suspected US drones have increasingly targeted North Waziristan, a bastion of Al-Qaeda fighters, the Taliban and the Haqqani network who attack the 113,000 US and Nato troops fighting in neighbouring Afghanistan.