Three missiles struck a house in the Khaisur area of the North Waziristan tribal region near the border with Afghanistan, said two intelligence officials on condition of anonymity because they were not authorized to speak to journalists.
The identities of the dead were not known.
America has fired more than 30 missiles this year at militant targets close to the Afghan border, killing scores of alleged insurgents. U.S. officials do not publicly acknowledge being behind the attacks. The missiles are fired from unmanned drones launched either from Afghanistan or — according to some media reports — from secret bases in Pakistan.
Pakistani officials protest the strikes, but the country's military is thought to provide intelligence for some of them.