MINNEAPOLIS (AP) — An oven used for heating may have caused a house fire in north Minneapolis that killed three young children, fire officials said Sunday. While the fire is under investigation, Fruetel said the oven door was open and that the fire started at or near the stove, the Star Tribune reported (http://strib.mn/1FNNOL5 ). The home's owner, Dung Tu, said the family, a mother and three children, had just moved into the rental and the natural gas heat had not yet been turned on. The fire chief said the 100-year-old home was last inspected in January and was outfitted with working smoke detectors.