A US drone aircraft killed 10 suspected militants in Pakistan's North Waziristan region near the Afghanistan border on Wednesday, security officials and residents said, the fifth such strike this year.
The unacknowledged Central Intelligence Agency drone programme, a key element in US counter-terrorism efforts, was apparently halted after a November Nato air attack from across the Afghan border killed 24 Pakistani soldiers enraged Pakistan.
The United States resumed attacks with the missile-firing drones in northwest Pakistan on Jan 10.
In Wednesday's attack, a drone fired two missiles at a house suspected of being a militant hideout in the village of Thapi, 15 km (10 miles) east of Miranshah, the main town in North Waziristan.
The building was completely destroyed and 10 suspected militants were killed, Pakistani security officials said.
"Almost all the men were burnt beyond recognition," a villager said after visiting the destroyed house.
"Dozens of militants arrived later and took over rescue work. They pulled out nine bodies," he said, requesting anonymity.
Security officials and villagers said the dead included foreign fighters but they did not specify their nationalities.
Several militant groups, including the Afghan Taliban and al Qaeda, have a presence in Pakistan's northwestern ethnic Pashtun regions, taking advantage of a porous border with Afghanistan to conduct cross-border attacks, or plot violence elsewhere.
North Waziristan is also an important base area for the Haqqani network, an Afghan militant faction allied with the Taliban which the United States says is one of its deadliest adversaries in Afghanistan.
While the Haqqani faction says it no longer needs a sanctuary in North Waziristan and has made enough battlefield gains in Afghanistan to stay there, it is known to still operate in the Pakistani border region.
A Pashtun tribal elder said militants usually avoided gathering, limiting groups to three or four people to minimise losses in the event of a drone attack. But they had dropped their guard recently.
"It has been freezing cold in the last few days and then there were no drones for some time. That's why the militants started living together and suffered heavy losses," the elder, who declined to be identified, told Reuters.
The use of the unmanned aircraft over Pakistan is opposed by most members of the public and Pakistani politicians, who regard the attacks as violations of sovereignty that produce unacceptable civilian casualties.
But despite its public stance, Pakistan has quietly supported the drone programme since President Barack Obama ramped up air strikes after taking office in 2009.