Forensic analysis and other information have enabled the U.S. military to verify that a key associate of Taliban chief Mullah Omar was killed in an airstrike in southern Afghanistan last week, a spokesman said Sunday.

The military is "very sure" it killed Mullah Akhtar Mohammad Osmani although it can't provide visual proof as his body was "obliterated" in Tuesday's attack on a vehicle traveling through Helmand province, said military spokesman Col. Tom Collins.

A Taliban spokesman has disputed that Osmani died in the attack, and identified another militant it claimed was killed.

Collins said Osmani was the highest-ranking Taliban leader killed by the U.S.-led coalition since the invasion of Afghanistan that ousted the hardline regime in late 2001 for hosting Usama bin Laden. He said Osmani's death would hurt militant operations.

Osmani was one of the two top Taliban military commanders in the south and southeast of Afghanistan and believed to be among Omar's top lieutenants.

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"He was hit by a precision air strike. The vehicle was destroyed and all the occupants were obliterated," Collins said. "We had him under observation for a good while, we knew he was in the vehicle. When that vehicle moved out of that built up area he was in, that's when we hit it."

"We checked various sources, and we are very, very sure it was him in that vehicle."

Collins said Osmani was identified through forensic analysis, but not through DNA tests. He said the type of analysis performed was classified information.

Purported Taliban spokesman Qari Yousef Ahmadi claimed the airstrike in fact killed Mullah Abdul Zahir, a group commander, and three other Taliban fighters.

"I confirm that Osmani is alive and is in Afghanistan," Ahmadi told The Associated Press by phone from an undisclosed location after the U.S. military announcement made Saturday.

But Qatar-based satellite channel Al-Jazeera, said that sources very close to the Taliban confirmed to its correspondent in Islamabad that, "Taliban leader Akhtar Mohammad Osmani was really killed with his companion Maulavi Abdul Zahir Baloushi and a third unidentified person."

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Helmand provincial police chief Ghulam Nabi Malakhail also said both Osmani and Zahir were killed in the airstrike, along with two other Taliban fighters.

The U.S. military only said Osmani and two associates were killed.

The Taliban militia has stepped up attacks this year, particularly in southern Afghanistan, and waged fierce battles with Western and Afghan forces. About 4,000 people have died in the violence, raising fears for the country's future and experiment with democracy after a quarter century of war.

The U.S. said Osmani played a "central role in facilitating terrorist operations" including roadside bombs, suicide attacks and ambushes against Afghan and international forces, and had been "utilizing both sides" of the Afghan-Pakistan border.

Analysts said his death could hamper preparations for an expected militant offensive in southern Afghanistan in early 2007.

The U.S. said Osmani was an associate of Usama bin Laden, Omar and Afghan insurgent leader Gulbuddin Hekmatyar, but Collins said he didn't know the last time Osmani had contact with any of the three.

During the Taliban regime that was ousted from power in late 2001 by U.S.-led forces, Osmani served as corps commander in Kandahar, the militia's seat of power, which would have placed him close to Omar, the Taliban's reclusive leader who has a US$10 million reward on his head.

In June, a man claiming to be Osmani — his face was concealed by a black turban — gave an interview to a Pakistani television network in which he said Omar and bin Laden were alive and well. He claimed to be receiving instructions from Omar.

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