A senior commander in the al Qaeda-linked Haqqani network, which Washington accuses of a series of bold attacks in Afghanistan, has been killed in a US drone strike, officials said.
Covert CIA drones are the chief US weapon against Taliban and al Qaeda militants who use Pakistan's lawless tribal areas as launchpads for attacking US troops in Afghanistan and plotting attacks on the West.
Pakistani officials said that 10 militants were killed on Thursday in a series of drone attacks, including two strikes that slammed into a compound north of Miranshah, the main town in the Pakistani tribal area of North Waziristan.
"Jamil Haqqani, an important Afghan commander of the Haqqani network, was the target and was killed," a Pakistani security official said on condition of anonymity.
A Pakistani intelligence official confirmed the killing and said Jamil was a coordinator of the Taliban-allied Haqqani network in North Waziristan. He said three other Haqqani fighters guarding the commander were also killed.
Defense secretary Leon Panetta for the first time this week publicly said the United States was waging "war" in Pakistan against militants, referring to the covert CIA campaign.
The latest salvo was fired on the day US special envoy Marc Grossman held talks with Pakistani leaders on strengthening their fragile alliance in the war on terror.
Confirming a Haqqani leader had died in North Waziristan on Thursday, a senior US official in Washington said it was "the most senior Haqqani leader in Pakistan to be taken off the battlefield".
The official named him as Janbaz Zadran, also known as Jamil, and said he had "played a central role in helping the Haqqani network attack US and coalition targets in Kabul and southeastern Afghanistan".
Pakistani officials said the slain commander was not a relative of Jalaluddin Haqqani, the Afghan warlord who founded the Taliban faction, or his son Sirajuddin Haqqani, who now runs the network.
But they said he was "very close to the top commanders including Sirajuddin".
Hours later a second attack hit the Birmal area in the neighbouring district of South Waziristan close to the Afghan border, killing six militants, a Pakistani security official said on condition of anonymity.
Another official said the attack happened as militants loyal to Pakistani warlord Maulvi Nazir, whose fighters are loyal to the Haqqanis, tried to move from one area to another near the border.
The United States blames the Haqqanis for fuelling the 10-year insurgency in Afghanistan, attacking US-led NATO troops and working to destabilize the Western-backed government of Afghan President Hamid Karzai.
Washington significantly stepped up demands last month on Pakistan to take action against the network, which it blames for a series of attacks including a 19-hour siege of the American embassy in Kabul on September 13.
The outgoing top US military officer, Admiral Mike Mullen, has called the Haqqani network a "veritable arm" of Pakistan's ISI intelligence agency and accused Pakistan of supporting attacks on US targets in Afghanistan.
But US action has been largely limited to US drone strikes.
More than 50 have been reported in Pakistan so far this year including dozens since Navy SEALs killed al Qaeda leader Osama bin Laden in the garrison city of Abbottabad, close to the capital Islamabad, on May 2.
Pakistan officially denies any support for Haqqani activities, but has nurtured Pashtun warlords for decades as a way of influencing events across the border in Afghanistan and offsetting the might of arch-rival India.
The Pakistani military says it is too over-stretched fighting local Taliban to acquiesce to American demands to launch an offensive against the Haqqanis.