WINONA COUNTY, Minn. (WKBT) -

The Winona County Sheriff’s Department is investigating what led to the death of a 57-year-old man who was found in a pool of blood in the backyard of a residence on Broadway and Center Streets in Rollingstone.

Authorities say they haven't ruled out a suspicious cause of death.

Winona County Sheriff Dave Brand said the man, whose name has not been released, was found dead Sunday at about 3:40 p.m. in the backyard of a home he was watching. The homeowners found him when they returned.

There was also a blood trail for about two blocks leading to a park where more blood and the man's glasses were found.

Stay with News 8 and News8000.com as more information becomes available.