QUANTICO, Va. (AP) — A Marine killed a male and female colleague in a shooting at a base in northern Virginia before killing himself, officials said.

It began with a shooting around 11 p.m. Thursday that left one dead at Marine Base Quantico, base spokesman Lt. Agustin Solivan said. That shooting led to a standoff between authorities and the suspect, who was barricaded in barracks at the base.

Authorities entered the barracks early Friday and found the suspect dead of a self-inflicted gunshot wound along with a second victim. Solivan could not say what prompted authorities to enter the barracks, which are at the base's officer candidate school.

No names were immediately released but Solivan said the suspect and both victims were Marines. Authorities believe the suspect was a staff member at the officer candidate school, Solivan said.

Solivan said the shooting was isolated to the school and authorities were confident there were no other casualties. The base was put on lockdown after the shooting but the lockdown was lifted early Friday. During the lockdown, residents were warned over a loudspeaker to stay inside.

The base, which is about 37 miles south of Washington, is also home to the FBI's training academy.

In 2010, the base was one of several targets of an ex-Marine reservist who, during five nighttime shootings, fired on military targets including the Pentagon. Yonathan Melaku, on two separate occasions, fired at the National Museum of the Marine Corps in Quantico. No one was injured and Melaku was ultimately sentenced to 25 years in prison.

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