Published: Dec 09, 2011 6:00 AM EST
Updated: Dec 09, 2011 4:22 AM EST

BLACKSBURG, Va. (AP) - An investigation is under way into the fatal shootings today at Virginia Tech.
    
A gunman killed a campus police officer in a school parking lot and was later found dead, with a gun nearby, in another lot.
    
Virginia Tech was the scene of the deadliest shooting rampage in modern U.S. history nearly five years ago.
    
In an ironic twist, the shootings took place on the same day Virginia Tech officials were in Washington, fighting a government fine over their alleged mishandling of the 2007 bloodbath that left 33 dead.
    
Before it became clear that the gunman in today's attack was dead, the school locked down the campus and used a high-tech alert system to warn students and faculty members to stay indoors.
    
Police say the officer was killed after pulling a driver over in a traffic stop. The gunman - who was not involved in the traffic stop - walked into the parking lot and shot the officer. Authorities won't talk about a motive.
    
The officer had served on the campus police force for four years. Police don't know if he had been specifically targeted.

The Virginia Tech police officer who was gunned down is being identified as a 39-year-old Army veteran and father of five.
    
The university said late Thursday that the officer was Deriek W. Crouse. He joined the Virginia Tech Police Department on Oct. 27, 2007. That was about six months after 33 people were killed at the school in the deadliest mass shooting in modern U.S. history.
    
Crouse previously worked at a jail and a sheriff's department.

About 150 students gathered silently for a candlelight vigil at Virginia Tech after a police officer was gunned down and the shooter apparently killed himself on campus.
    
The students showed up Thursday night on a field facing the stone plaza memorial for the victims of the 2007 massacre. In that bloodbath, 33 people were killed in the deadliest mass shooting in modern U.S. history.
    
Though the official candlelight vigil was moved to Friday evening, many turned out anyway to show their support. One student came forward to invite everyone back for Friday night's event. He shouted, "Let's go!" The crowd responded, "Hokies!"

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