A man charged with killing an Auburn University student told police he tried to rape her before he shot her, according to documents read in court Monday as several thousand of her peers gathered for a memorial service.

Lauren Burk, an 18-year-old freshman from Marietta, Ga., lived in an apartment near campus and was found on a roadside about 5 miles from the university; her car was later found ablaze in a campus parking lot.

The documents read in court, sworn to by a police detective, said suspect Courtney Lockhart, 23, described verbally and in writing how he abducted Burk from the university, robbed her, drove her around, told her to take her clothes off and shot her with a handgun. He also described driving the car back to campus and setting it on fire.

His attorneys, including Joel Collins, could not be reached for comment after business hours Monday.

At the memorial service, an estimated 6,000 students gathered in the basketball arena to remember Burk.

"Her smile was contagious, all of us know that, and she could brighten a room," said Alison Penuel, president of the Delta Gamma sorority at Auburn, which Burk joined in August. "She touched all of us in a special way."

When Penuel began struggling to speak through tears, Auburn President Jay Gogue got up and put his arm around her to help her finish. Sniffles and crying could be heard in the auditorium between speakers.

Lockhart, who lived in rural Smiths, was arrested Friday in Phenix City after a chase. Auburn police said he was linked to the Burk case by a photograph and other evidence that has not been disclosed.

Lockhart served with the Army in Iraq in 2004 and 2005 and was court-martialed, sentenced to confinement and given a bad conduct discharge in December 2006 for charges including assault, military officials have said.

Also Monday, police in North Carolina investigating the slaying of the student body president of the University of North Carolina focused on a suspect pictured in several surveillance photos using Eve Carson's ATM card.

Police released two new photos Monday evening of a young man wearing jeans and a black coat inside a convenience store. Chapel Hill Police Chief Brian Curran said the man appears to be the same person seen in two ATM surveillance photos released Saturday.

In those pictures, the suspect is seen in a baseball cap and hooded sweat shirt driving a sport utility vehicle that may be Carson's Toyota Highlander.

Carson, 22, of Athens, Ga., was found last week lying on a street about a mile from campus after police received two 911 calls reporting gunshots. She had been shot several times, including once in the right temple. Her SUV was found the next day a few blocks from her home.

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The Associated Press contributed to this report.