December 8, 2011 at 6:02 PM EST - Updated June 26 at 1:50 AM
BLACKSBURG, VA (RNN) - Two people have been killed on the campus of Virginia Tech, the scene of the worst mass shooting by a single gunman in U.S. history. One of the victims is a campus police officer.
The state police, the FBI, a SWAT team, emergency response teams and police dogs have swarmed the campus searching for the unidentified shooter. So far, none has been found.
An emergency response team was called in to the bottom floor of the student center, where students have been sequestered during the campus-wide lockdown.
Nearby Montgomery County Schools have also been placed on lockdown. Police are searching nearby cars for the suspect.
The shooting appears to be the result of a traffic stop gone wrong, when the alleged shooter opened fire on the female police officer. The officer returned fire before succumbing to her injuries.
"Shortly after 12 p.m. today, a Virginia Tech officer stopped a vehicle on campus during a routine traffic stop in the Coliseum parking lot near McComas hall. During the traffic stop, the officer was shot and killed," according to a statement by Mark Owczarski, director of news and information at Virginia Tech.
A person who matches the description of the gunman was spotted sitting at a bus stop; however he was not arrested. The alleged shooter is described as a white male wearing gray sweatpants, a gray hat with a neon brim, maroon hoodie and backpack.
The shots were fired near an off-campus parking lot, and then about an hour later at the performing arts center. A person near the center apparently surrendered to authorities, but he was not arrested.
The second victim, believed to be a student, was found in another parking lot near Duck Pond Drive, after the shooter fled on foot.
More shots were reported in at least two other locations on campus. However, police said those sounds were trash dumpsters banging together during pick-up.
Law enforcement blocked the back gates to the campus, and police requested any unassigned units to report to the south gate. At least 15 squad cars were reported on campus.
Law enforcement have investigated reports of suspicious vehicles and suspicious persons in their search for the gunman.
Finals for the students, which were supposed to start Friday, have been postponed.
This is not the first shooting on the Virginia Tech campus. On April 26, 2007, Seung-Hui Cho killed 32 people - five faculty members and 27 students - and wounded 25 others before committing suicide.
Cho, who was a senior, shot two people at West Ambler Johnston Hall, a dormitory before crossing campus to Norris Hall, a classroom building.
Cho chained the main entrance doors shut to prevent anyone from exiting the building and hindering police from entering the building. Students jumped from windows to escape the shooter.
Cho killed himself as police stormed the building.
In August, the campus was placed on lockdown after reports of a gunman were made to campus police. No gunman was ever found.
Ironically, testimony had been scheduled today in an appeal hearing requested by the university for fines levied against it for its handling of the 2007 shooting.
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