The cause of a fire at an auto repair shop in Huntsville is undetermined. The fire happened at around 2:30am Monday. The shop sustained about $100-thousand worth in damages. No one was injured at the time.  Huntsville/Lake of Bays Fire Chief Steve Hernen says they believe the cause to be accidental, but because of the amount of damage the fire caused, they can’t confirm for sure. The auto repair shop was located at 1041 Brunel Road.