A Marine who was assigned as a student to the School of Infantry-West died during a training exercise at Camp Pendleton Thursday, officials said.

The unidentified Marine was participating in a night live-fire training at the base, according to spokesman Maj. Joshua J. Pena.

It is unclear how exactly the Marine died, however.

“An investigation into the circumstances of the death is ongoing and the command is fully cooperating with the investigation efforts,” Pena said in a statement. “(School of Infantry – West) is providing support to the family and peers of the deceased during this difficult time.”

No further information about the victim or the incident have been released.