Fire investigators say a smoldering cigarette was the apparent cause of a house fire that killed a 17-year-old high school student in Genesee County.

Erik Mooney died of smoke inhalation Friday after he was found collapsed at the top of a staircase. His 41-year-old mother and 15-year-old brother were able to escape the early morning fire after being awakened by a smoke detector and barking dog.

The county's emergency management services coordinator, Timothy Yaeger, says the victim's mother, Judy Clark, had been smoking in an enclosed porch about half an hour before the fire started.

The boys' stepfather, Scott Clark, was not home at the time.

Erik was a student at Oakfield-Alabama High School.