WALKER (AP) -- Authorities say a 21-year-old man whose body was found in a fish house during the eelpout festival in northern Minnesota last month died of accidental carbon monoxide poisoning.

Cass County Sheriff Tom Burch released the ruling of the Ramsey County medical examiner's office Wednesday.

Samuel Schooley of Bemidji was reported unresponsive Feb. 25 at the popular festival celebrating the ugly, bottom-dwelling fish on Leech Lake. Schooley was pronounced dead at a Park Rapids hospital.