KCCI.com, IA 08-14-07 Damage Thwarts Fire Investigation Investigators Probe Sorority House Fire DES MOINES, Iowa -- Extensive damage is making it difficult for investigators to find the cause of a fire at an Iowa State University sorority house. The fire broke out at about 7 p.m. Sunday and raced through the third floor of the Alpha Chi Omega house. Fire investigators said they will be working with investigators from the insurance company to learn what started it.