Updated

A Utah doctor serving a term of up to life in prison for drugging and drowning his wife so he could carry on an affair with another woman was found dead in the Utah State Prison Sunday.

According to a press release from the Utah Department of Corrections, 60-year-old Martin Joseph MacNeill was found unresponsive in the outdoor yard of the Olympus Facility of the Utah State Prison Sunday morning.

While an investigation will determine the exact cause of death, the press release states there are no "obvious signs of foul play."

Related stories...

Officers found MacNeill near the greenhouse in the Olympus yard and began CPR, but responders were not able to revive him and he was ultimately declared dead at the facility.

The Unified Police Department is handling the investigation into MacNeill's death, and the Utah Department of Corrections' Law Enforcement Bureau will assist.

MacNeill has been incarcerated at the Utah State Prison since September of 2014, the press release states, after being convicted of first-degree murder, second-degree obstruction of justice, and second-degree forcible sex abuse.

Read more from FOX 13 Salt Lake City.