KALAMAZOO, Mich. (AP) -- Kalamazoo authorities say someone started a fire at a low-income apartment complex that killed three young children and say they've ruled out an accident involving electricity, natural gas, a furnace or water heater.
Public Safety Assistant Chief Brian Uridge said Thursday that the Feb. 18 fire "initiated with human involvement."
The fire killed 3-year-old twins Tevin and Ty'nitha Williams and their 1-year-old sister Tyonna Henderson, who were home alone with their 4-year-old sister.
Uridge says a criminal investigation continues and says the Kalamazoo County prosecutor's office will eventually decide whether to bring any charges.
He says reports of an explosion were based on a flashover that happened when a resident trying to rescue the children opened a door and fed oxygen to the fire.