By Michael Hansberry (staff@latinospost.com) | First Posted: Oct 08, 2012 12:44 PM EDT

Friends and family of a slain college freshman in Alabama are left stunned after a police shot and killed the unarmed student.

Gilbert Thomas Collar, 18, of Wetumpka, Ala. was killed early Saturday morning on campus at the University of South Alabama in Mobile, after an officer heard a bang on a window at campus police headquarters and went to investigate. Mobile police said Collar was a "muscular, nude man" who was"acting erratically" and had assumed a "fighting stance" and chased the officer before being fatally shot in the chest.

The school released a statement saying the officer tried to retreat numerous times to defuse the situation before opening fire.

Collar's mother, Bonnie Smith Collar, is saying her son never touched the officer.

"I have been told by someone involved in the investigation that the videotape shows my son never touched the police officer," she said in a phone interview with the Associated Press.

The university said the officer tried to retreat numerous times to defuse the situation before opening fire.

Smith said she has received conflicting reports on what might have happened before the shooting and would not discuss it.

"Whatever caused the incident was something that made him act not in his normal personality,
she said.

"Really, it just upsets me that there's no other way to apprehend an unarmed student rather than shooting him. I don't understand that," said sophomore Tyler Kendrick.

Another student, Joshua Frye expressed similar concern over the officer's use of a handgun.

"What I feel is that a cop has more than a gun," Frye said.

The officer has been placed on leave and an autopsy is being conducted to determine if Collar had drugs or alcohol in his system.

This makes the second person to be killed on USA's campus since last year.

A candlelight vigil is scheduled for 6 p.m. Tuesday at Wetumpka High School. His mother said funeral arrangements have not yet been made yet.