Nigerian extremist leader surfaced in 2010

NAIROBI, Kenya -- The leader of the Nigerian Islamic extremist group tugged on his winter hat and said with a sneer: "I will sell women," he sneered.

The man is Abubakar Shekau, the leader of Nigeria's most feared terror group, Boko Haram. It is Shekau who threatened in a grainy video this week to sell nearly 300 schoolgirls his fighters abducted in northeast Nigeria.

Even before the mass kidnapping, the U.S. government offered up to a $7 million reward for information leading to the arrest of Shekau, whom the U.S. has labeled a specially designated global terrorist.

In lectures heard in scratchy recordings, Shekau says holy war is the only way to bring change for Muslims in Nigeria as he urges his followers to carry out assassinations and bombings.