KABUL, Afghanistan — Afghanistan asserted Wednesday that the Taliban's reclusive leader, Mullah Mohammad Omar, died more than two years ago in a Pakistani hospital — an announcement that injects new uncertainty into the country's fragile peace process.
If confirmed, the surprising news of the death of Mullah Omar would remove a unifying figure for the insurgents, who are believed to be split on whether to continue the war or negotiate with the government of President Ashraf Ghani.
In Washington, the U.S. government said they considered the report of the Taliban leader's death credible, though it was not confirmed by the Taliban or Pakistan.
The Afghan government's announcement came just two days before a second round of peace talks between the government and negotiators claiming to speak for the Taliban leadership. It also raises questions about the authority of Taliban representatives who attended a first round of talks in Pakistan on July 7, as well as earlier informal meetings in Qatar and Norway.
Abdul Hassib Sediqi, the spokesman for Afghanistan's National Directorate of Security, said Mullah Omar died at a hospital in the Pakistani city of Karachi in April 2013.
"We confirm officially that he is dead," Sediqi told The Associated Press.
"He was very sick in a Karachi hospital and died suspiciously there," he said, without elaborating.
A statement later Wednesday from the office of the president said it had confirmed the death based on what it called "accurate information" and insisted that Mullah Omar's demise would benefit peace efforts.
"The Afghan government believes that the ground for the Afghan peace talks is more solid now than before and thus calls on all armed opposition groups to seize the opportunity to join the peace process," the statement said.
The one-eyed, secretive head of the Taliban sheltered Osama bin Laden's al-Qaida in the years leading up to the Sept. 11, 2001, terror attacks, and then waged a decade-long insurgency against U.S. troops after the 2001 invasion that ended Taliban rule. He fled into Pakistan on a motorcycle and was never seen again.
Mullah Omar was born in the southern Uruzgan province in the early 1960s and became a mullah, or preacher, in Kandahar, the southern city that would later become the capital of the Taliban movement he went on to lead.
In 1979, when the former Soviet Union sent in troops to support a leftist government, Mullah Omar took up arms. When civil war erupted after the anti-Soviet war ended in 1989, Mullah Omar became leader of the Taliban movement that took power in 1996 and spread a severe interpretation of Islam across the country.
Sediqi said the Afghan government had been aware of Mullah Omar's death for two years and said it had made it public on a number of occasions.
However, the earlier claims lacked the authority and detail of Wednesday's announcement by Kabul officials. They usually came from secondhand sources, were made behind closed doors, or lacked direct confirmation from the government. The Taliban denied previous claims.
It was not immediately clear why his death was only announced now. Pakistan's Foreign Ministry said it had no information about the announcement.
A White House spokesman, Eric Schultz, said the U.S. had concluded the reports were credible and said U.S. intelligence agencies were looking into the circumstances.
A former Taliban minister who was once close to Mullah Omar said he died of tuberculosis and was "buried somewhere near the border on the Afghan side." He spoke on condition of anonymity so as not to jeopardize his standing with the Taliban, who do not want individual members to speak to the media.
A Pakistani security official, also speaking on condition of anonymity because he wasn't authorized to brief journalists, had earlier dismissed the reports of Mullah Omar's death as "speculation" designed to disrupt peace talks.
It is widely believed that the Taliban has split between supporters and detractors of the peace talks as their war on the Afghan government has intensified in recent months. Many observers believe that the war is being directed on the battlefield by leaders who believe they can defeat government forces.
The Taliban, or at least a faction of the insurgent group, released a statement on July 15 purportedly made by Mullah Omar in support of the peace process.
"Whether he is dead or alive is important because he is the collective figure for the Taliban," said a Western diplomat with connections to the Taliban leadership. "If he is dead, it would be much more difficult to get negotiations with the Taliban because there would be no collective figure to rally around and take collective responsibility for entering peace talks."
The diplomat spoke on condition of anonymity because he was not authorized to brief journalists.
Taliban insurgents have spread their war from their traditional southern and eastern heartlands bordering Pakistan to northern Afghanistan this year.
In recent weeks, the insurgents have taken control of remote districts in Badakhshan province, and continue to launch mass attacks on districts in Kunduz province, a strategically located region bordering Tajikistan.
The strategy has spread Afghan military resources thin after U.S. and NATO forces ended their combat mission at the end of last year.