The air strike took place in South Waziristan district where the military in October launched an air and ground offensive to flush out Taliban militants.
The "hideout in Shawal mountains was targeted after a tip off received that terrorists were hiding there," the military said in a statement.
The death toll could not be verified independently as the area is under military control.
Pakistan's military is engaged in offensives against Islamist fighters across much of the northwest including tribal areas bordering Afghanistan, a region branded by Washington the most dangerous place on Earth.
About 30,000 troops poured into South Waziristan in mid-October to try to dismantle strongholds of the Taliban leadership, enraging militants who have responded with a surge of bombings and other attacks.
More than 3,000 people have been killed across Pakistan in attacks by Islamist militants since July 2007.
Washington believes militant safe havens in Pakistan's tribal belt must be eliminated if Al-Qaeda is to be defeated and the eight-year war against the Taliban ended in Afghanistan.
US Marines are leading a major offensive against a Taliban bastion in Helmand province, billed as the biggest since the 2001 US-led invasion and the first test of President Barack Obama's strategy to drive out the hardline militia and reassert government control.
In other violence, suicide bombers attacked two police stations in northwest Pakistan, killing a police station chief and wounding six other policemen, police officials said.
In the first attack, a gunfight broke out when two would-be suicide bombers stormed into a police station in Mansehra, police said.
One of the attackers was shot dead and the other fled, station chief Waheed Khan told AFP.
"We have cordoned the area and are searching for the second attacker," Khan told AFP.
Ali Raza, another police official, told AFP that bomb disposal staff were defusing the explosives strapped to the dead attacker's body.
An AFP photographer at the scene saw the body of the attacker lying in the police station and heard gunshots as police rushed after the second attacker.
In a separate attack in the neighbouring mountain town of Balakot, a suicide bomber killed police station chief Khalil Khan and wounded three policemen, local police official Sabir Ullah told AFP.
Prime Minister Yousuf Raza Gilani "strongly condemned" the attacks, his office said in a statement.
Militants have stepped up attacks against the police force which is not as well equipped as the military.
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