The State Fire Marshal’s office says this week’s early-morning housefire in southwest Iowa’s Page County was an act of arson. Authorities in Shenandoah received a call about the blaze at 602 Fifth Street, just before 5 A.M. Tuesday.

Upon arrival at the single-family rental home, the fire department learned two children were still inside the burning structure. Firefighters rescued a six-year-old male and four-year-old female, but both suffered from severe smoke inhalation, and were flown to a burn unit at an Omaha hospital. A third juvenile was treated at a local hospital and released Wednesday.

Investigators determined the fire was intentionally set in the laundry room located toward the rear of the home, but they still don’t know what caused it, or who may have started it. Officials say family members have been cooperating fully during the on-going investigation. The home sustained extensive damage and is considered to be a total loss.