WASHINGTON - Al-Qaeda's number two Atiyah abd al-Rahman has been killed in Pakistan, the United States said on Saturday, claiming another "tremendous" blow to the group following the death of Osama bin Laden.
A senior US official said that Rahman was killed in tribal Waziristan on August 22 after being deeply involved in directing operations for Al-Qaeda. The official did not divulge the exact circumstances of his death.
Local officials in the tribal region however told AFP last week that a US drone strike on August 22 on a vehicle in North Waziristan killed at least four militants. It was not clear if the two incidents were connected.
The senior US official, speaking on condition of anonymity, said the death of Rahman would be deeply felt by Al-Qaeda because the group's new leader Ayman al-Zawahiri had relied on him heavily since US Navy Seals killed Osama.
Rahman's death represents "a tremendous loss for al Qaeda," the senior official said, speaking on condition of anonymity.
"The trove of materials from Osama's compound showed clearly that (Rahman) was deeply involved in directing Al-Qaeda's operations even before the raid," the official said.
"He had multiple responsibilities in the organisation and will be very difficult to replace."
The United States does not publicly confirm details of drone attacks but its military and the CIA in Afghanistan are the only forces that deploy the unmanned Predator aircraft in the region.
Washington has called Pakistan's semi-autonomous northwest tribal region the global headquarters of Al-Qaeda, where Taliban and other Al-Qaeda-linked networks plot attacks on NATO forces in Afghanistan.
The Washington Post cited unnamed officials in July as saying that evidence taken from Osama's compound suggested the Al-Qaeda founder was concerned about the impact drone attacks were having on his organisation when he died.
The death of Rahman represents another success for President Barack Obama's intensified and often clandestine operations against Al-Qaeda, particularly in the northwestern tribal regions in Pakistan which Washington says is the group's lair.
Bin Laden was killed in his compound in Abbottabad in a daring raid by US special forces soldiers deep into Pakistan in May, and the soldiers seized large amounts of intelligence about the group's operations.
The death of Rahman comes as the United States gears up to mark the 10th anniversary of Al-Qaeda's most spectacular attack, on September 11, 2001 on US landmarks in Washington and New York which killed nearly 3,000 people.
In his weekly radio and Internet address on Saturday, Obama called on Americans to recreate the national unity that emerged after the attacks, and noted that "We're taking the fight to Al-Qaeda."
In July, US Defence Secretary Leon Panetta said that the "strategic defeat" of Al-Qaeda was "within reach" and that 10-20 key operatives had been targeted in Pakistan, Yemen, Somalia and north Africa.
"Now is the moment, following what happened with (Osama) bin Laden, to put maximum pressure on them because I do believe that if we continue this effort that we can really cripple Al-Qaeda," he said.