SIOUX FALLS - Investigators say they should be able to pinpoint the cause of a house fire in Sioux Falls last month that killed three children.

Authorities got their first look inside the burned-out home on Tuesday. Sioux Falls Fire Rescue investigator John Daniels tells the Argus Leader newspaper that the fire's origin and cause might be determined in as little as a week.

KELO-TV reports that an accelerant-sniffing dog was brought in for a second time to search for any evidence of gasoline or other fuel, and again did not find anything.

The fire early on Dec. 22 killed 16-year-old Michael Hensley, 12-year-old Savannah Coon and 6-year-old Alivia Coon. The children's mother and her husband escaped with minor injuries by leaping from a second-floor window. The mother, Rhiannon White, faces drug charges.

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