A train transporting crude oil exploded in a giant fireball yesterday in North Dakota after hitting another train that had derailed. No injuries were reported, although the accident sent more than 2,400 people living within a five mile radius of the crash site to hastily set up shelters in Fargo.

New sources report that a westbound BNSF Railway train hauling grain derailed, causing a fiery explosion but no injuries. That train was then struck by a BNSF Railway eastbound oil train, which also derailed and exploded. At least ten cars of the second train were set ablaze. A Fargo Fire Department spokesman said the second train, which was 111-cars long, sent a giant fireball hundreds of feet into the air, with smoke visible for approximately 25 miles.

The incident has renewed concerns about the safety of transporting crude oil by railway. The partial derailment of an oil train in Alabama last month resulted in a fire that took emergency crews days to extinguish. Earlier this year, a train carrying crude oil derailed and exploded in Quebec, killing 47 people and destroying dozens of buildings.

A proposal by the Association of American Railroads to retrofit older tank cars that carry hazardous materials with safety features has been met with resistance by the oil industry, which says the changes could cost railroad companies billions of dollars.The fixes include protective steel jackets, thermal protection and pressure relief valves, which could cost billions of dollars. Oil shippers, likely to be saddled with the costs of retrofits, oppose some of the changes proposed by the association.

Shipments of crude oil in North Dakota have risen by 67 percent over the past year, due to a boom in the state's shale oil production.

The National Transportation Safety Board, Federal Railroad Administration and Pipeline and Hazardous Materials Safety Administration will conduct a joint investigation into the incident.