One version of bin Laden's pictures shows him with a full head of wavy gray and black hair, and a trim beard. No previous photograph had shown him without a head-dress covering his hair. The pictures were posted on the US state department's Web site.
The second 'aged processed' mug shot of bin Laden shows him with the long flowing beard that has been his trademark, although much more gray than previously seen.
The FBI said its artists modified facial features and changed the grooming and clothing preferences, hoping that people might recognise him, or any of the other terrorists.
Despite a $25 million reward for information on bin Laden's whereabouts, US officials say they have not had confirmed information about the Al Qaeda leader in more than eight years.
Bin Laden is wanted by the US in connection with the September 11, 2001 terror attacks on the World Trade Centre and the Pentagon, and the 1998 bombings of the US embassies in Tanzania and Kenya.
Images: Digitally enhanced pictures of Osama bin Laden. Photographs: US state department/FBI
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