COLUMBUS, Ohio — Exploding freight cars full of ethanol made for a dramatic early morning scene in Ohio’s capital today, but officials said the train derailment that led to a hurried evacuation of an urban neighborhood could have been much worse.

The National Transportation Safety Board dispatched a 10-person team to investigate the derailment on the Norfolk Southern Corp. tracks, which led to spectacular explosions and the burning of three tank cars each carrying 30,000 gallons of ethanol.

Officials said they don’t know yet what caused the accident, which occurred in an industrial area near Interstate 71, north of downtown. The explosions were felt for blocks and sent flames shooting high in the air.