Pravin Varughese, the 19-year-old student of Southern Illinois University, died due to hypothermia, according to the results of a preliminary autopsy conducted Wednesday. The body was discovered in the woods near Buffalo Wild Wings in Carbondale Feb 18. He was reported missing Feb 13.

Jackson County Coroner Thomas Kupferer said that there's no evidence of foul play in the death of the criminal justice major from suburban Chicago. Kupferer said that the results of Varughese's blood samples and toxicology test are still pending.

Pravin Varughese was last seen with his cousin and roommate at a house party in Carbondale Feb. 12. The college sophomore left the party with an acquaintance just before midnight. An argument reportedly prompted Varughese to get out and escape into the woods. Carbondale police have not yet determined the nature of the dispute. They believe that Varughese got out of the car all by himself.

His sister, Priya Varughese, 20, said that phone records showed Pravin called his friend in Chicago at 12:30 p.m. The friend told her that her brother sounded like he may have been running or having an argument during the call.

According to the Heartland StormTeam, temperatures were low (10 to 19) the night Varughese went missing, WSMV reports.

"We just miss him so much," says Priya. "We don't think he did this on his own we really feel like someone else is involved. We just want justice to be served. My brother was a great guy he always had us laughing."