Story highlights Lance Cpl. Sara Castromata and Cpl. Jacob Wooley were shot and killed Thursday

Marine base officials believe Sgt. Eusebio Lopez shot them before killing himself

The shooting at Quantico follows the deaths of seven Marines in Nevada last Monday

Authorities detail the careers of Castromata, Wooley and Lopez

They were three young Marines, decorated with awards and with seemingly bright futures ahead.

But the promise of two of them was cut short by the third Marine, who shot them -- and then turned the gun on himself, authorities say.

Late Saturday night, authorities released the names of the three Marines involved in the Thursday night shooting at the Marine Corps base in Quantico, Virginia.

They were Lance Cpl. Sara Castromata, Cpl. Jacob Wooley and Sgt. Eusebio Lopez.

Authorities said Lopez was the gunman.

The shooting stunned the military community. It came as the Corps grieves another tragedy: the deaths of seven Marines in a training exercise in Nevada on Monday.

Marine Sgt. Eusebio Lopez was identified as the gunman in the deadly shooting at Quantico.

The Marine Corps detailed the careers of the two Marines who were shot:

-- Lance Cpl. Sara Castromata, 19, of Oakley, California, served as a warehouse clerk. She joined the Marines in 2011 and was promoted to her current rank in February. Her awards include the National Defense Service Medal, Global War on Terrorism Service Medal and Good Conduct Medal.

-- Cpl. Jacob Wooley, 23, of Guntown, Mississippi, was a field radio operator. He joined the Marines in 2010 and was promoted in July. Wooley's awards include the Navy Meritorious Unit Commendation, Marine Corps Good Conduct Medal, National Defense Service Medal, Global War on Terrorism Service Medal and Sea Service Deployment Ribbon.

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They also released information on Lopez:

-- Sgt. Eusebio Lopez, 25, of Pacifica, California, was a tactics instructor at the base's Officer Candidates School and specialized as a machine-gunner. He joined the Marines in 2006 and received at least 10 awards, including the Combat Action Ribbon and the Humanitarian Service Medal. He had deployed in support of Operation Iraqi Freedom and in support of Operation Enduring Freedom.

The shooting remains under investigation by the Naval Criminal Investigative Service.