Omaha, NE – An Omaha couple found dead in their home last week were victims of accidental carbon monoxide poisoning, Omaha police said Monday.

The bodies of Mark and Phyllis Duranski were discovered Friday after friends became concerned when Phyllis Duranski, 73, failed to meet them for a concert.

Two of the couple’s children called a locksmith to open the front door of the home, which is near 218th and Pacific Streets. Once the door was opened, police officers entered and discovered Mark Duranski, 63, dead in the upstairs master bedroom, according to a police report. Phyllis Duranski was found in the upstairs bathroom.

Officers with the Omaha Police Department’s Criminal Investigations Bureau determined that carbon monoxide had entered the home after a car was accidentally left running in the attached garage. Police said the car had run out of gas.