The fire was Thursday afternoon at a house near 144th Avenue and Hascall Circle, and the fire department says the people inside escaped unhurt.
In classifying it an accident, investigators say the home had what they call many "non-conforming" modifications, with two, separate, accidental ignition sources identified in the area of fire origin.
Firefighters reported heavy smoke and flames from the rear of the wood framed, single family home.
The Red Cross was on scene to assist residents after the fire, which took about ten minutes to bring under control.
(Image from Omaha Fire)