FORT WORTH -- Firefighters knocked down a blaze Monday afternoon at Cooper's Old Time Pit Bar-B-Que in the Stockyards, a fire department official said.It was reported about 3:30 p.m. at the restaurant, 301 Stockyards Blvd., according to reports. Engineer Tim Hardeman, fire department spokesman, said at about 4:15 p.m. that the flames were under control, and later that it was extinguished.Hardeman said an employee "noticed the temperature in one of the pits was about 100 degrees above normal.""When he looked into the pit," Hardeman said, "he saw flames and attempted several times to extinguish the fire. The fire kept growing and the worker called 911."About 20 people, including customers and staff, safely evacuated the single-story building, Hardeman said.The flames, however, reached the attic and crews had to pull down part of the ceiling, Hardeman said.Damage was estimated at $20,000. Hardeman said a manager told him that he hoped repairs could be made quickly so that the restaurant could reopen soon.The restaurant, just north of Billy Bob's Texas, is one of four locations operated by the popular Llano-based Cooper's Old Time Pit Bar-B-Que.