Antonio Whitehead, 21, said he heard the fire alarm go off in the dorm and thought it was a routine event.
"All of a sudden, I felt the crowd move a little faster. And a police officer with a machine gun or something told everyone to start moving a lot faster," he said.
Seevakumaran had attended the university from 2010 through the fall semester as a business student. His roommates told detectives that he had shown antisocial behavior but had never shown any violent tendencies, Beary said.
According to Florida records, his only adult arrest in the state was in 2006 for driving with a suspended license.
Morning classes were canceled, but most campus operations resumed around noon.
Associated Press writers Mike Schneider in Orlando and Freida Frisaro in Miami contributed to this report.
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