MOBILE, Alabama -- A University of South Alabama student was nude and acting erratically early this morning before a university officer fatally shot him outside the campus police station.

The officer shot Gilbert Thomas Collar, 18, of Wetumpka, one time in the chest, USA spokesman Keith Ayers said during a news conference this afternoon on the campus.

The officer, whose name has not been released, has been placed on paid administrative leave pending the outcome of an investigation.

The university has asked the District Attorney's Office to investigate the shooting. The Mobile County Sheriff's Office will help with the investigation.

The university held a news conference outside the police station at 3 p.m. today. Ayers read from a prepared statement.

He would not answer questions about if it is suspected that Collar was under the influence of drugs or alcohol.

"We can't comment beyond the statement," he said.

The officer encountered Collar after there was a loud bang on a west side window of the police station at 1:23 a.m. today.

"When an officer exited the station to investigate, he was confronted by a muscular, nude man who was acting erratically," Ayers said. "The man repeatedly rushed toward the officer and verbally challenged the officer in a fighting stance."

The officer drew his gun and ordered Collar to stop, Ayers said.

"The officer retreated numerous times in an attempt to calm the situation," Ayers said. "The individual continued to press toward the officer in a threatening manner."

Collar kneeled for a brief moment before rising and then rushing and chasing the retreating officer, Ayers said.

He said the officer shot Collar after the student continued to rush the officer in a threatening manner and ignored the officer's commands to stop.

"The individual fell to the ground, but he got up once more and continued to challenge the officer further before collapsing and expiring," Ayers said.

A few students gathered outside the police station during the news conference. Some were concerned that the officer shot and killed Collar.

Macy Meadows, 19, of Fairhope, said that when she arrived on campus early Saturday morning an officer was not allowing traffic near the police station.

She said she had to park and walk to her dormitory. At the time, she said she didn't realize there had been a shooting on campus.

She said she later received an email from the university in regard to the shooting.

"If he didn't have a weapon, I feel like he shouldn't have been shot," said Meadows, a sophomore.

Kinsey Miller, 19, of Pace, Fla., said she considers the campus to be safe, but she has concerns that are similar to Meadows'.

"I don't think it was handled properly," she said. "It makes me feel real differently about how police handle situations on campus."

Thyrie Bland is on Facebook and Twitter.