PRATT — Investigators are unable to discover the cause of a fire that killed a Kansas mother and her four children.

WIBW reports that the Kansas Office of the State Fire Marshal says the cause of the Jan. 25 blaze in Pratt has been classified as undetermined. Twenty-two-year-old Charee Wheatley died in a hospital two days after her children died in the fire. The children — Reece, Timmy, River and Harley — ranged in age from a few months to 6 years.

The Fire Marshal’s Office says their investigators spent three days on the scene, examining evidence, sifting through debris and interviewing witnesses. They determine the fire started in the basement of the home. Investigators noted that no fire alarms were found in the house.