According to Chico fire investigators, the flames were reported at 2:19am Friday. They say there were two girls, 8 and 9, home alone at the time. They say one child was sleeping when she heard a beeping noise, and it woke her up. She rushed outside where her sister was sleeping in the car, and the two ran down the street to a neighbor's home. The neighbor called 911. Cal Fire, Chico, and Butte County firefighters rushed to the home on 121 York Avenue, and knocked the flames down quickly. It is estimated that the fire caused at least $50,000. The cause is under investigation. Chico Police are investigating why the children were left alone at the home. They are in the care of CPS.