CSX Transportation says it believes the derailment of one of its coal trains Friday in Washington was caused by a procedural error.
The railroad says the brakes on the rail cars were not secured properly and that caused them to roll out of a nearby yard and over a section of track that was closed for repairs. Ten cars of an 89-car train derailed in the accident, which occurred on a bridge over the Anacostia River. Seven cars full of coal ended up in the water.

Clean up crews have been working to remove the derailed cars from the bridge and ensuring the structure of the bridge is safe.
Meanwhile, CSX officials report they are conducting water quality tests around-the-clock. At this time, all water conditions remain normal.
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