ROGGEN, Colo. – Investigators say the cause of a fire that killed 500,000 chickens at a Weld County egg farm on April 30 was “accidental,” the Greeley Tribune is reporting. Despite the official findings, the company that operates the farm continues to investigate the incident. According to the Tribune, the Boulder Valley Poultry egg farm produced about 25 percent of the eggs sold in Colorado prior to the fire. The chickens killed in fire produced about 250,000 eggs per day, or about one-eighth of Colorado’s total egg production.