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"Mullah Omar died two years and four months ago owing to tuberculosis," a former Taliban minister told The Express Tribune. "He has been buried on Afghan side of the border."

The Taliban told the BBC it will release a formal statement today.

Omar has been "out of the public eye" for the past 13 years, according to Al Jazeera. He became the Taliban's "supreme leader" in 1996 and reportedly had close ties to Osama bin Laden. The United States has a bounty of $10 million on Omar, the BBC reports.