Story last updated April 9, 11:03 p.m. EDT
WASHINGTON — A Marine sentry at Camp Lejeune, N.C., who shot and killed a fellow Marine likely did so accidentally, the Pentagon said Wednesday.
An investigation by the Naval Criminal Investigative Service continues into the Tuesday incident, which occurred less than a week after a mass shooting that claimed four lives and injured 16 at Fort Hood, Texas.
The base identified Lance Cpl. Mark N. Boterf, 21, as the Marine who was shot and killed.
“Indicators point to a negligent discharge situation,” Pentagon spokesman Col. Steve Warren told reporters Wednesday. “It appears right now to have been an accident.”
Both Marines were on duty at the main gate of the North Carolina base when the shooting took place inside a small guard shack at 5:30 p.m. local time, said Capt. Joshua Smith, a spokesman for the base.
Boterf was shot once in the chest with an M4 rifle, Smith said. Following immediate resuscitation efforts at the scene by first responders, Boterf was declared dead 40 minutes later at Naval Hospital Camp Lejeune.
“It is being ruled an isolated incident,” said Smith, who stressed that the shooting is not being looked at as a potential act of terrorism. “No one else was in danger, and the base never went into lockdown. The base was never in danger, nor did the front gate ever close.”
The shooter has not been identified, but Smith said he was a man.
Boterf, a native of Crawley, Texas, was assigned to the 2nd Radio Battalion of the II Marine Expeditionary Force and only temporarily serving on guard duty, according to the base.
Smith estimated that during that time of day there can be seven to 10 sentries guarding the large gate. The guards typically carry M4 assault rifles, he said.
Accidental discharges by military members, while rarely resulting in death, are not unheard of. Marine Col. Daren Margolin was relieved of duty in October after accidentally firing his handgun in his office at Marine Corps Base Quantico, Va. In one famous incident, then-Lt. Col. David Petraeus was accidentally shot in the chest in 1991 by a soldier who reportedly tripped and discharged his rifle during a live fire exercise.
Including the surrounding community, the Camp Lejeune population is about 170,000. The base is home to the II Marine Expeditionary Force, 2nd Marine Division, and 2nd Marine Logistics Group, among others, according to the base website.