People are forced to evacuate a Yuba City gym after a fire breaks out inside the building. It happened just before 1:30 a.m. Friday morning at Northside Fitness on Kelton Way. A night manager and 4 customers were in the gym when the blaze started. Fortunately, everyone was able to make it out safely. When crews arrived on scene they had a hard time locating the fire. Flames blew through the roof after firefighters started poking holes for ventilation. The fire was eventually tracked to an attic area above the men's locker room. No word on how much damage the fire caused. The cause of the blaze is still under investigation.