Gunman at University of Texas Austin Identified as Sophomore Math Major Colton Tooley

Sept. 28, 2010— -- A 19-year-old math major got dressed in a suit and a ski mask and fired off several rounds from an AK-47 assault rifle today, sending the campus of the University of Texas at Austin into a lockdown before taking his own life in a library, police said.

Colton Tooley was seen running through the campus this morning as classes started. He was wearing a dark business suit, carrying a rifle and shooting rounds into the air.

Police told ABCNews.com that the investigation had moved off campus to a "house associated with the shooting."

Tooley was a sophomore math major at UT, concentrating in actuarial sciences, according to the student directory. Public records indicate that Tooley lived in South Austin, about 10 miles away from the university. Calls made to a number at that address went unaswered, but recorded answering machine message identified Tooley as a resident.

Just before noon, a campus lockdown that had been in effect since around 8 a.m., was lifted, and police ended a search for a possible second suspect.

"The armed suspect is dead. No other injuries have been reported," UT President Bill Powers wrote in a campus email.

Tooley was found dead on the sixth floor of the library from apparently self inflicted wounds, police said.

An email and text alert was sent to students and faculty around 8 a.m., just as the day's first classes were beginning, warning that an "armed subject was reported last seen at Perry Castaneda Library" and telling students to remain in place.

"I was walking to class, a little late," senior Robby Reeb told ABCNews.com. "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."

Reeb said he was outside between two buildings and had to choose which one to enter to avoid the shooter.

Students reported hearing bursts of gunfire. Police confirmed Tooley was carrying an AK-47, a military-grade combat rifle. Authorities said there were currently two crimes scenes: the library where the gunman was found dead, and an area outside where he fired shots into the air.

At a press conference police said they had not yet determined a motive.