Huge fire after US oil train derails in North Dakota
A plume of thick black smoke could be seen many miles away and explosions were heard.
No injuries were reported, but officials ordered the evacuation of about 300 people from the nearby town of Casselton as a precaution.
An investigation into the incident has been launched.
A spokeswoman for the North Dakota Department of Emergency Services said the last 50 wagons of the train had been uncoupled, but another 56 remained at risk.
The derailment, after a collision involving another goods train, is reported to have happened near an ethanol plant.
Emergency and fire-fighting crews have been sent to the scene.
Police Sgt Tara Morris said although there was no immediate danger to residents of Casselton, they were being evacuated as a precaution in case the wind direction changed.
Correspondents say it is the latest in a string of incidents that have raised alarm about a rise in crude oil traffic on the railways.