NORFOLK, Va. (AP) - A sixth Somali man has been sentenced to life in prison for his role in the hijacking of a yacht that left all four Americans aboard dead.
    
The owners of the Quest, Jean and Scott Adam of Marina del Rey, Calif., along with friends Bob Riggle and Phyllis Macay of Seattle, were shot to death in February, several days after being taken hostage several hundred miles south of Oman. They're the first Americans to be killed in a wave of piracy attacks near Africa in recent years.
    
Eleven men have pleaded guilty to piracy in the case. Ahmed Sala Ali Burale was a guard who says he tried to stop the shooting once it started. He and pirate leader Mohamud Salad Ali received the mandatory life sentences Tuesday.

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