RIVER FALLS, Wis. (AP) — An autopsy has been done on a University of Wisconsin-River Falls freshman but investigators still don’t know how the 19-year-old died in her dorm room.

Kersten Greene, an Eau Claire native, was found dead Thursday. Police say there’s no sign of trauma or injury.

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WQOW-TV reports that toxicology results will take several weeks. Police say there is no threat to the general public.

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Within the last week or so, two 19-year-old female students have died in Winona, Minn. The death of a St. Mary’s University student was due to natural causes and a Winona State University student’s death does not appear to be suspicious.

A 23-year-old University of Wisconsin-Milwaukee student also died in recent days, after falling down stairs at a party.

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