Employees at the North Liberty Fareway grocery store were hard at work this morning cleaning up and restocking shelves following a fire Sunday morning. Rich Beckwith, district superintendent, said the fire was caused by an overheated refrigerator case in the store’s produce section. Firefighters were called to the store at 615 Westwood Drive at 10:32 a.m. Sunday for alarms going off and smoke coming from the store’s roof. Crews discovered that the entire store had filled with smoke and that the refrigerator case was on fire.