The Ramsey County medical examiner's office has ruled the death of a University of St. Thomas student an accidental drowning.
The body of 19-year-old Dan Zamlen was found in the Mississippi River in early May, nearly a month after he disappeared after leaving a party.
The St. Paul Police Department says the investigation into Zamlen's disappearance and cause of death is now closed.
But St. Paul police spokesman Paul Schnell said investigators are still looking into the case.
"There is a secondary, but related investigation that is currently ongoing related to issues of furnishing of alcohol to underage persons, that may have been connected to Dan Zamlen's death, and that's what's being explored by investigators at this point in time," Schnell said.
Friends told police that Zamlen had been drinking and left the house party upset about an incident there.
Zamlen, a native of Eveleth, was 18 when he disappeared.
Police spokesman Sgt. Paul Schnell says the results of Zamlen's autopsy report, including the results of toxicology tests, are protected by the Minnesota Data Practices Act and will not be released.
(The Associated Press contributed to this report.)