Omaha Fire Investigators have ruled the fire near 129th and West Maple as an accident.

The Fire Investigation Unit has determined that it's highly probable the fire was caused by the usage of space heaters, which were used throughout the mobile home.    

It was determined that the fire started in the living room where one of the space heaters was located. There was a smoke detector in the kitchen, but it did not have a working battery.

Investigators say the official cause of death for the three month and three year old boys will be released once the autopsies are complete. The mother of the two children, 18 year old Champain Harn is now in serious condition.

Harn's 15 month old daughter remains hospitalized.