A fire caused extensive damage to a Cary restaurant early Thursday morning. Assistant Fire Chief Loren Cone tells WNCN firefighters were called to On the Border on Walnut Street just after midnight, and found heavy fire in the front of the building. A volunteer firefighter from Cove City tells us he spotted the flames and banged on the windows to make sure no one was inside. He says he called 911 to alert Cary firefighters. The building was not occupied and no one was injured. The investigation into where the fire started and what caused it is still underway. Firefighters were on scene for hours, and are expected to continue their work throughout the morning.