The Oklahoma State Bureau of Investigation says its agents are assisting the Garvin County Sheriff's Office in the investigation. The OSBI says its agents were called Saturday after the worker found the body near Elmore City, about 60 miles (96 kilometers) south of Oklahoma City.
The OSBI says an autopsy will determine the man's cause of death but that there are "obvious signs of trauma" that suggest a homicide.
Authorities have not yet released the man's name or announced any arrests in the case.
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