AUSTIN, Texas (AP) — Police say they're investigating two crime scenes on the University of Texas campus after a gunman opened fire inside a library then fatally shot himself.
Austin Police Chief Art Acevedo says authorities also continue to investigate reports of a possible second suspect Tuesday morning.
Officials say a man fired an automatic weapon on the sixth floor of the Perry-Castaneda Library early Tuesday before killing himself.
No other injuries have been reported but Acevedo says police also are investigating what he describes as a second crime scene outside the library where shots were fired.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
AUSTIN, Texas (AP) — A gunman opened fire Tuesday inside a University of Texas campus library then fatally shot himself, and police are searching for a possible second suspect, university police said.
A man fired an automatic weapon on the sixth floor of the Perry-Castaneda Library early Tuesday, UT police spokeswoman Rhonda Weldon said.
"He subsequently shot himself. He is deceased," she said, adding that no one else was reported injured.
Senior Robby Reeb told ABCNews.com he was rushing through the campus late for a class when the shooting happened.
"I was walking from the business school, and a guy sprinted past me screaming, 'There's a guy with a gun.' I looked up and saw a man in a ski mask, wearing a suit, and carrying an assault rifle. And I called 911."
Police and university officials urged students to stay indoors. The university canceled classes for the day.
"A suspected shooter in PCL library is dead. Police are searching for possible second shooter. Lock doors, do not leave your building," the university said in an e-mail alert to students and staff.
Weldon said there was no report that the possible second suspect may have been armed, but that police are taking all precautions and keeping the campus locked down.
Investigators are trying to determine what led to the gunfire at the UT campus at Austin, which is one of the largest in the country with nearly 50,000 students.
Law enforcement from campus police, Austin police and the state Department of Public Safety rushed onto campus at the first reports of the shooting. Tank-like armored vehicles were positioned near the library. A DPS helicopter circled the campus overhead.
"It's chaos right now," student Micah Geisenberg told CNN.
The Perry-Castaneda Library is one of several on the campus and is one of the busiest undergraduate libraries.
Tuesday's shooting is not the first at the school.
On Aug. 1, 1966, Charles Whitman went to the 28th floor observation deck at the UT clock tower in the middle of campus and began shooting at people below. He killed 16 people and wounded nearly three dozen before police killed him about 90 minutes after the siege began.
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