Norfolk Southern Railroad says the fire from a train derailment and explosion on Columbus' North side is now out. Crews are working to clear the train cars from the site of Wednesday morning's derailment and blast near the state fairgrounds. Authorities decided to allow the three tank cars carrying ethanol to burn before spraying a chemical foam to prevent the blaze from re-igniting. The National Transportation Safety Board says high speed and track conditions do not appear to be factors in the accident.