NAPA (KRON) — Police are investigating the death of a 60-year-old man after he was found unresponsive at a house in Napa Monday.

Police and firefighters responded to a medical call the 1000 block of Foster Road at 1:11 p.m. after the victim’s brother found him.

The house had a strong odor of propane, and the victim’s brother was overcome by carbon monoxide while he tried to administer first aid, according to police.

Firefighters rescued the man who had called police. He was transported to Queen of the Valley Medical Center where he’s listed in stable condition, according to police.

Inside the home, firefighters found a propane tank with a heater attached. Police say there are no signs of foul play.

Further details are unavailable at this time.

Anyone with additional information is asked to contact Detective Pete Piersig at (707) 257-9514.