Three Florida State University students were injured when a gunman opened fire inside and outside the school's packed library early Thursday morning, authorities said.

The gunman, identified by authorities as Myron D. May, was shot and killed by responding officers outside the Strozier Library after he fired a .380 semi-automatic weapon at them, authorities said. More than 30 rounds were fired by the gunman and officers.

"At the time, as you can imagine, Strozier Library was packed with students studying for final exams. Our estimates right now are anywhere from three to four hundred students who were studying," said Florida State University Police Department Chief of Police David Perry at a 6 a.m. news conference.

May is a graduate of FSU and is an attorney. He's from Ohio and moved to Florida at a young age, police said at a 3 p.m. news conference. May moved to Texas after graduating, but returned to the campus area three weeks ago expressing fears that he was being targeted by the government, police said. Those details are still under investigation.

"The person just, for whatever reason, produced a handgun and began shooting students in the library," Perry said.

The Associated Press reported:

Abigail Taunton told the AP that May had recently been staying at a guest house she owns in a rural area in the Florida Panhandle. She said police interviewed her husband, David, after the shooting.

Two of the victims are students and one is a FSU employee. All three are male. WCTV, citing the Tallahassee Police Department, reported on Wednesday that one victim is in critical condition; another in stable condition; and the third was victim grazed by bullet, treated at scene, and released.

"We are too frequently and too often waking up to incidences like this around the country," Tallahassee Mayor-Elect Andrew Gillum.