The United States offered bounties of US$5 million each for the arrest of two Americans, including a man known as the "rapping jihadist", said to have joined Islamic militants in Somalia.
Omar Hamami and Jehad Mostafa were named under the State Department's Rewards for Justice programme for their ties to the al-Qaeda linked al-Shabab militants.
Hamami, 28, a former Alabama resident, moved to Somalia in 2006 and began to work for Shabab recruiting young trainees through his English-language rap songs and videos, the State Department said.
He was indicted in 2009 by an Alabama district court for providing support to a terrorist organisation, and two years later he was placed on a US Treasury blacklist freezing all his assets in the United States.
Hamami also served as a military commander under Mostafa, a former resident of San Diego, California, who left for Somalia in 2005 where he provided media support and led foreign fighters.
Mostafa is also on the FBI's most wanted terrorist list, and was charged in 2009 in a California district court with providing material support to Shabab.
Hamami - better known as Abu Mansoor al-Amriki or "the American" - said late last year that he had split from the insurgents, who want to kill him.
"Amriki would like to accept the honour of most wanted list and thanks everyone," he said in a message on an unverified Twitter account in November following his listing by the FBI on their Most Wanted Terrorists list.
He spends his days denouncing his former Shabab colleagues as corrupt, and refers to himself as the "former poster boy" of the group.
Since it was set up in 1984, the Rewards for Justice programme has paid out over US$125 million to about 80 people for information leading to the arrests of those designated as terrorists in the US.