Mount Prospect police are investigating the death of a 39-year-old Des Plaines man found in a vehicle early Friday morning in the area of River Road and Tano Lane.
A village police officer discovered Edward Kuzniar at 12:37 a.m. Friday while stopping to investigate why a Chevrolet Malibu was on the side of the road with its hazard lights on.
According to police, the officer observed a male front seat passenger exit the vehicle and begin to act suspiciously after seeing the police car. The female driver of the vehicle then exited and the officer had a conversation with both subjects, police said.
During that conversation, police said, the officer learned of Kuzniar in the car's back seat.
The Mount Prospect Fire Department responded to the scene and transported Kuzniar to Glenbrook Hospital, where he was pronounced dead, according to police.
The other occupants of the Malibu voluntarily returned to the Mount Prospect Police Department for further investigation and are cooperating with police.
Police Cmdr. John Wagner said the two individuals indicated they had spent the better part of the day with Kuzniar and that he had been drinking excessively. They said they initially thought he was just intoxicated and had passed out.
They are not considered suspects, and there were no obvious signs of trauma or foul play, Wagner said.
After an autopsy, the Cook County medical examiner's office ruled Kuzniar's death to be undetermined, pending toxicology results.