A gunman stormed the campus at Florida State University in the early hours of Thursday morning, wounding three students before being shot dead by police.
One of the victims was said to be in critical condition after the shooting, which took place shortly after midnight at a library on the university's main campus in Tallahassee.
Police spokesman Dave Northway said a call was received about an "armed subject" near the Strozier Library at 12.30am ET. Officers rushed to the scene, where they surrounded the shooter outside the library and ordered him to drop his gun. Instead, he shot at them, at which point the officers opened fire, killing him instantly.
A law enforcement official, speaking on condition of anonymity, told The Associated Press the shooter had been identified as Myron May, a graduate of the university who went on to attended law school at Texas Tech University.
Steven Dawson, a 19-year-old student, told NBC News that he was working on the library's third floor when he heard shouts about a shooter in the building. "Everyone just dropped everything and started running," he said. Along with several others, he ran down a fire escape; once outside they heard a series of around 10 gunshots coming from the area of the library entrance.
"Everyone took off running," Dawson said. "I've never seen more people screaming and running."
Classes at the university were cancelled on Thursday and it was announced at a morning police press conference that the officers involved in the shooting were put on leave pending an investigation. Questions have also been raised about the level of security on the campus.
"This person for whatever reason produced a handgun and then began shooting students in the library," Florida State University Police Chief David Perry told reporters.
The university president, John Thrasher, said in a statement that the shooting was thought to be an isolated incident.
"The Florida State University community is extremely saddened by the shootings that took place early this morning at Strozier Library, in the very heart of campus," Thrasher said. "Out thoughts and prayers are with the families and loved ones of all those who have been affected... we are increasing security measures and providing a strong law enforcement presence on and around campus today."
A series of shootings at schools and colleges have led to impassioned debates about gun ownership in the United States. The National Rifle Association, the leading advocate for gun rights, was the target of furious protest following the Newtown massacre in December 2012, in which 20 children and six staff were killed at Sandy Hook Elementary School in Connecticut in the worst school shooting in US history.
In the wake of Sandy Hook, the Obama administration put forward proposals to reduce gun violence, including a ban on assault weapons and a tightening of background checks. However to the president's ire, the measures were defeated in the Senate.
Since then, shootings have continued unabated. In October, a 15-year-old gunman killed four students in the cafeteria of a high school near Seattle before committing suicide. The previous month, a student at Indiana State University shot another inside a residence hall.
This year there have been 27 such incidents on school or university campuses in the US, 13 in the month of January alone.
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