NCIS Investigating Marine Sergeant's Death by Gunshot While On Duty

A Marine assigned to a Georgia submarine base was killed by a gunshot wound to the head last month while he was on duty, officials confirmed.

Sgt. Derek J. Diesel died on Aug. 18 after he was shot at Kings Bay Naval Submarine Base, Georgia. His death, which was not initially disclosed by the Marine Corps or Navy, was reported by the Naval Safety Center this week. The center tracks serious military accidents and mishaps.

Diesel's death remains under investigation by the Naval Criminal Investigative Service, Gina Levy, a spokeswoman for Marine Corps Forces Command, said. The incident was first reported by Marine Corps Times on Tuesday.

This is the second on-duty gunshot incident in about a month. In August, a Marine was paralyzed from the neck down during a live-fire exercise at Marine Corps Air-Ground Combat Center 29 Palms, California.

Related: Marine Shot and Killed at Marine Barracks Washington

The sergeant was assigned to the Security Force Regiment unit that was located aboard the submarine base, she added. Marines with the antiterrorism and security unit are assigned to guard high-value naval installations that host nuclear vessels.

Diesel, who was 25, joined the Marine Corps in 2014 after attending the Virginia Military Institute, according to his obituary. He was married with a 2-year-old daughter, it states.

"Derek was a hardworking, passionate leader both at home and throughout his service in the Marine Corps," the obituary adds. "He loved his family, friends, and country."

Marine officials did not provide any additional details on his death, citing the ongoing investigation.

A fundraiser set up for his family has raised $6,700.

-- Gina Harkins can be reached at gina.harkins@military.com. Follow her on Twitter @ginaaharkins.

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