LOS ANGELES (CBS) — A Marine is being held as a suspect in the apparent murder at Camp Pendleton of a 19-year-old Marine from Canoga Park, the Naval Criminal Investigative Service said Monday.

Lance Cpl. Mario Arias was found dead in his barracks room Sunday morning.

A second Marine was found outside the barracks after jumping from a third-story balcony, the NCIS said. He is being treated for his injuries and held as a homicide suspect.

Arias was an air-crew trainee with Marine Light Attack Helicopter Training Squadron 303, Marine Aircraft Group 39, 3rd Marine Aircraft Wing.

The suspect’s name was not released.