A San Bernardino County Fire fire fighter was injured Tuesday afternoon in a commercial fire in Hesperia. A fire broke out around 12:30 PM in the old San Bernardino County Sheriff station located at 9393 Santa Fe Avenue East. Arriving units called for a second alarm. The fire fighter was injured when the roof gave way and he fell through the roof. According to scanner traffic, the victim fell through the two story building ending up on the main floor. He was quickly rescued by other personnel and then flown by SBCo Fire H-325 to Arrowhead Regional Medical Center for treatment.