GILLETTE, Wyo. (AP) — Authorities in Campbell County have released three men arrested for manslaughter after an autopsy revealed the alleged victim died of a heart attack.

The three men were released Friday before they were scheduled to make a court appearance on charges of involuntary manslaughter.

The three men were arrested this past Thursday after 44-year-old Peter Huke was found dead at Action Mechanics. Huke worked for the company and lived on site.

Authorities say the three men had an altercation with Huke several hours before Huke was found dead.

County Coroner Tom Eekhoff says an autopsy shows Huke died of a heart attack.

The determination prompted Campbell County authorities to release the arrestees.