At least five people were killed and several others injured in a U.S. drone strike launched in North Waziristan on Friday evening, security forces said.
According to security sources, a US unmanned aircraft fired two missiles on house suspected of being a militant hideout in Shawal area of the agency, killing four people.
Firday's U.S. drone strike is the 39th of its kind in Pakistan in 2012. Since the beginning of this year, at least 274 people have been killed in such strikes.
Though most of the killed are believed to be suspected militants, the U.S. drones do sometimes kill innocent people, which has led to strong opposition from the Pakistani side.
Drone strikes are controversial in Pakistan, where many politicians condemn them as a violation of sovereignty. But the United States sees them as a key tool in the fight against terrorism.