The missiles destroyed a vehicle and compound in North Waziristan.

Local security officials said unmanned US aircraft fired at least six missiles at the targets in Mir Ali village, 25 kilometres east of Miranshah.

"At least 15 militants were killed in a US missile strike, which targeted a vehicle and a compound," a senior security official told AFP.

"Four missiles hit the vehicle and two struck the compound," he added. Security officials had initially put the death toll at six.

The United States does not confirm drone attacks, but its military and the Central Intelligence Agency operating in Afghanistan are the only forces that deploy the aircraft in the region.