(CNN) -- He is merciless toward opponents, secretive to the point of being a recluse and a true believer in the cause of global jihad. And from his hideout somewhere in southern Somalia, Mukhtar Abu Zubayr, the emir of Al-Shabaab, has planned numerous terror attacks, including the deadliest in Kenya since the U.S. Embassy bombing in 1998. Zubayr, who is also known as Ahmed Abdi Godane, already has a price on his head. In 2012, the U.S. State Department authorized a reward of up to $7 million for information on his whereabouts. But he has 15 years on his terror resume, and according to information provided by a well-placed source in Mogadishu who has extensive knowledge of Al-Shabaab, he "is ruthlessly eliminating real and imagined rivals" within the group.
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Al-Shabaab chief Mukhtar Abu Zubayr has a reputation for being secretive, merciless
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Zubayr wants his group to be able to deliver devastating attacks beyond Somalia
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He formally declared Al-Shabaab an affiliate of al Qaeda
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Zubayr's tactics have led to dissent in his group, which he has ruthlessly suppressed
Others in @placeholder's leadership disagreed, saying the group had to gain greater public support before such a move.