GWINNETT COUNTY, Ga. -- Investigators have identified a woman whose remains were found in an abandoned Subway sandwich shop in the vacant food court at Gwinnett Place Mall.

The woman's body was found in a back room on the morning of December 21 by a maintenance worker. There were no obvious signs of trauma to her body, but police said they considered it a suspicious death and that she'd been dead for about two weeks.

Investigators released a sketch of the woman and were able to determine who the woman was through tips and the help of the Gwinnett County Medical Examiner's Office.

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According to Gwinnett County Police, the woman was identified as 19-year-old Silling A. Man of Lawrenceville, Ga.

Man, a sophomore majoring in psychology at Georgia State University, was reported as missing on Oct. 8 by a family member. Shortly after that, she had returned home and the missing person case was closed.

But the family said that Man ran away again shortly after that. No other missing person case was filed, police said, but the family had no contact with her after Oct. 10. She did pick up a check from the clothing store where she had worked at Perimeter Mall on Nov. 20, according to police.

Man's other actions after she ran away in October remain a mystery. It's known that while she was enrolled in classes at GSU in the fall, she didn't sign up for the current, spring semester.

It's believed that Man died about two weeks before her body was found. The death has not been ruled a homicide, but it is still under investigation.

Investigators hope toxicology tests will help determine what may have led to the death.

“They want to look into her history," said Gwinnett County Police Cpl. Michele Pihera. "They want to look and see who she’s been hanging out with, see what her movements have been, from, at least, a two-month period of time, and hopefully that will give us some more answers into this investigation.... She did have some injuries. And she was only 19 years old. So it's very unlikely that she died of natural causes. We believe that there is somebody out there who knows the circumstances around her death.”

Anyone with information on Silling Man's whereabouts from mid-October through mid-December is asked to call police at 770-513-5300.