15 Marines and one sailor were aboard an AAV, amphibious assault vehicle, during a training this past summer. As the vehicle was making its way back to the U.S. Navy ship, the USS Somerset, it began to sink and the men started to flee the vehicle. Some of the personnel aboard were able to be rescued but most of them drowned with the sinking craft. A total of eight Marines and one sailor died, and their remains were recovered a week later. Lt. Gen. Karsten S. Heckl, Commanding General, relieved Lt. Col. Michael J. Regner of his duties after he “compiled a substantial amount of information and data which formed the basis for Heckl’s decision,” according to the Marine Corps statement on Tuesday.