Investigators say they’ve determined the cause of last week’s housefire in northeast Iowa that killed a mother of seven. Waterloo Fire Rescue officials and the Waterloo Police Department released their findings on Monday about the fatal fire Friday morning that killed 37-year-old Sandra Rasmussen.

The fire was ruled accidental. A scented oil warmer is blamed for the fire. The oil warmer was powered by a light bulb and placed on a table in the living room. Items around the warmer caught fire and it spread quickly throughout the house. An autopsy determined the Rasmussen died of burns and smoke inhalation.

The funeral for Rasmussen is planned for Thursday.

By Jesse Gavin, KCNZ, Cedar Falls