NEW HYDE PARK, N.Y. (CBSNewYork/AP) — Autopsy results show a Northwestern University student from Long Island drowned, but the medical examiner does not know whether the death was accidental.

Investigators said there were no signs of foul play when the body of 18-year-old sophomore Harsha Maddula was found in the water in Wilmette Harbor around 7 p.m. Thursday, the school said in a statement posted on its website.

The Cook County Medical Examiner’s office said Friday that the manner of his death was undetermined because there was not enough information to rule it an accident, a homicide or a suicide.

WCBS 880 Long Island Bureau Chief Mike Xirinachs reports

Maddula’s wallet with a university identification card and his cell phone were also found on the body, according to the school.

“On behalf of Northwestern University, I extend our deepest sympathies to Harsha’s family and to his many friends at Northwestern. Our hearts and thoughts are with them,” University President Morton Schapiro said in a statement released by the university.

Maddula was last seen after midnight Saturday. A relative said he went to the party with several friends and disappeared after he and others left for another party.

His parents, Prasad Maddula and Dhana Lakshmi Maddula, and other relatives arrived in Evanston, Ill. on Monday to join the search for the pre-med engineering student, who had been recently diagnosed with diabetes.

Friends said it changed his outlook. He even dropped out of school for a semester.

Maddula’s parents, along with the student’s uncle, Sam Maddali, on Wednesday announced a $25,000 reward for information leading to the student’s whereabouts. They were standing at Wilmette Harbor, where their son’s body was found, when they made the announcement.

Maddula’s mom fainted and was rushed to the hospital upon learning her son’s body had been found. She called his voicemail everyday since his disappearance just to hear his voice, CBS 2’s Chris Wragge reported.

Maddula was a brilliant and hard-working student who wanted to be a doctor. Friends who knew him in New Hyde Park where he grew up said he loved soccer, music and science. He worked summers in his family-owned pharmacy.

“It’s such a tragedy,” said family friend Sabrini Mahboob. “All the hopes, the aspirations as parents we have for our kids, it’s gone.”

“I remember him running around playing in the schoolyard across the street. It’s a parents worst nightmare,” Mahboob added.

“I drove him to high school. He was a very good boy,” said neighbor Chaite Mohan.

Maddula’s family hasn’t announced any funeral arrangements.

Toxicology tests won’t be back for 6 to 8 weeks.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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