DEKALB, Ill. (AP) -- Authorities say human remains found in a park where a missing Northern Illinois University student is believed to have gone were badly burned.

NIU spokesman Joe King cited police as saying the state of the remains complicates the process of determining whether they belong to 18-year-old Antinette "Toni" Keller.

Friends say they last saw the freshman art student from Plainfield on Oct. 14 as she headed to the forested park just south of the 25,000-student university in DeKalb.

DeKalb Police Chief Bill Feithen told reporters earlier Tuesday that investigators were now treating the case as a homicide investigation.

He says there's someone out there who "committed this," and he says they aren't in custody.

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