A US drone has killed 11 insurgents, mostly Afghans, at a compound in Pakistan's tribal region, near the north-western border with Afghanistan.
The attack was the second reported US missile strike in two days.
A Pakistani security official confirmed the attack and said the death toll may rise.
The ABC reports the building belonged to Maulvi Shakirullah, a commander in the forces of Pakistani warlord Hafiz Gul Bahadur.
Bahadur is an ally of the Haqqani network.
On Wednesday, a US drone killed five fighters at another compound in North Waziristan, according to Pakistani officials.