An early-morning attack on a village southwest of Mogadishu resulted in the deaths of U.S. citizen Omar Hammami, known as al-Amriki, and British citizen Osama al-Britani, the BBC reported.
The two top militants had had a falling out with al-Shabaab after their ally, veteran Somali Islamist Sheikh Hassan Dahir Aweys, split from the group in June, the BBC said. The group has been hunting down Aweys' allies since his split.
Aweys is in the custody of the U.N.-backed government.
The U.S. State Department offered a $5 million reward to information leading to the arrest or conviction of al-Amriki, who grew up in Daphne, Ala., the son of a Sunni Muslim father from Syria and a Southern Baptist Christian mother.
Al-Britani was a British national of Pakistani origin.
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