Authorities say a heart attack killed a 37-year-old upstate New York man who lost six children in a house fire two years ago.

Lewis Carl Smith II was found unresponsive in a vehicle late Saturday in the village of Fort Edward, 45 miles north of Albany. Fort Edward police told the Post-Star of Glens Falls ( http://bit.ly/LZJE5B) that an autopsy showed heart disease caused his death.

A fire ripped through Smith's Fort Edward home in June 2010, killing six of his seven children, who ranged in age from 1 to 12 years old.

Officials said the fire was sparked by a wrong fuse installed in first-floor outlet. Smith and his girlfriend Samantha Cox, the mother of three of the children, were injured trying to rescue the kids. He and Cox separated after the fire.