The medical examiner said Monday that the two men found dead in a rural Springfield, Minnesota farmhouse on Dec. 20 died from carbon monoxide poisoning.
The New Ulm Journal reports Dennis Potter, who owns the house, found his son, 30-year-old Nathan Potter, and his son's roommate, 23-year-old Adam Jensen, unresponsive around 1:40 p.m. and called 911.
One of the men was found in an upstairs hallway while the other was lying on a couch in the family room, according to a separate report.
Nathan Potter and Jensen were pronounced dead at the scene.
The Springfield Fire Department responded to ventilate the home. The Brown County Sheriff's office said Monday that carbon monoxide had leaked from the furnace due to a damper not functioning properly.
It's unclear if there were carbon monoxide alarms inside the home. Minnesota law requires approved carbon monoxide alarms in all single family homes and multifamily apartment units.