The drones fired four missiles at the compounds in Karikot and Doogh areas near Wana, the main town in South Waziristan Agency, TV news channels quoted officials as saying.
The men killed in the strikes were believed to be members of the Taliban faction headed by Mullah Nazir, whose men frequently carry out cross-border attacks on US and foreign forces in Afghanistan. Drones continued to hover over the area after the strikes.
Al Qaida-linked militant commander Ilyas Kashmiri was reportedly killed in a US drone strike in the same area earlier this month. However, US officials have said his death cannot be confirmed.
There have been more than 35 drone strikes in Pakistan's tribal belt bordering Afghanistan this year.