Authorities are investigating the death of a 25-year-old man on the Leech Lake reservation in Cass County.

Officers responded just before midnight Thursday to a report of a man being brought to the Cass Lake Indian Health Services hospital after a “serious assault,” according to the Cass County Sheriff’s Office. The man, of Cass Lake, died a short time later.

Authorities say they have searched two homes in Pike Bay Township. The Leech Lake Tribal police and the Minnesota Bureau of Criminal Apprehension continue to investigate.