The maintenance worker was found unconscious at a southwest Atlanta apartment complex on Monday morning, and police are trying to figure out what happened to him.
Atlanta police say residents found the man near the leasing office at the complex on Hank Aaron Drive SW, and his truck was parked nearby.
According to investigators, a threatening letter was found next to the man's body. The victim, who has not been identified, was taken to Grady Memorial Hospital.
Police say the incident may have been caught on surveillance video, so they're looking into that possibility.