The attack took place in Pasalkot village in North Waziristan, a stronghold of Taliban and al-Qaeda-linked fighters.
Two missiles were fired at a compound on Thursday, where Hakimullah Mehsud, (pictured), the Pakistani Taliban chief, was believed to have been.
"We had information that he was around there. We're checking on whether he was killed," a Pakistani security official, who declined to be identified, told Reuters news agency.
However, a Taliban spokesman told Pakistan's Dawn TV that Mehsud was safe and had left minutes before the assault.
Alan Fisher, Al Jazeera's correspondent in Pakistan, said the US were likely to view the operations as a "huge success".
"The use of drone strikes in Pakistan is highly controversial but there's no sign of the Americans stopping them any time soon," he said.
"They will regard this latest operation as a huge success - targeting and killing what they say were a number of militants."
Mehsud took over as leader of the Pakistani Taliban five months ago, after Baitullah Mehsud, his predecessor, was killed in a similar US drone attack.The US has increased drone attacks in Waziristan since a suicide bomber crossed over Pakistan's border and killed seven CIA employees in an attack in eastern Afghanistan on December 30.
A video was later released showing Hakimullah Mehsud sitting beside the CIA bomber, a Jordanian double agent, creating the impression that his group played a major role in the second biggest attack on the CIA in its history.
The attack was the seventh suspected US missile assault in the tribal district this month.
North Waziristan houses Taliban and al-Qaeda fighters as well as members of the Haqqani network, a powerful group known for staging attacks on foreign troops in Afghanistan.
The US government has called on Islamabad to step up its efforts against Taliban- and al-Qaeda-linked fighters who cross over into Afghanistan.
The Pakistani army recently completed an offensive against the Taliban in South Waziristan, which borders North Waziristan.