TOWN OF BIRNAMWOOD, WI (WTAQ) - An autopsy is scheduled Wednesday for a 53-year-old Shawano County man, while his 20-year-old son awaits a possible charge of killing him.

Donald Johnson of Birnamwood died early Tuesday.

Sheriff's captain Tom Tuma said it's believed that a "series of aggressive acts" caused the death.

His son Joshua is being held in the Shawano County Jail as the incident remains under investigation.

Tuma said the suspect called 911 to report the death -- and a dispatcher managed to keep him on the phone until deputies arrived and found the victim's body.