A US drone fired two missiles into a militant compound in Pakistan's northwestern tribal belt, killing four militants on Sunday, security officials said.
The missiles targeted the compound in Shaktoi area in South Waziristan, a Pakistani security official, speaking on condition of anonymity, told AFP.
"The US drone fired two missiles into a militant compound in Shaktoi and we have reports that four militants have died," he said.
An intelligence official and a local administration official also confirmed the missile strike.
Sunday's attack was the second within 24 hours after a similar drone attack in the region killed 12 militants on Saturday.
South Waziristan, considered a militant stronghold, was the scene of a major Pakistani offensive last year.