About 25 train carriages have derailed in north-western Montana, with no injuries or evacuations reported, authorities said.
The carriages, which were not believed to be carrying anything hazardous, derailed near the town of Paradise along the Clark Fork River, a police spokesman said.
Firefighters and representatives of Montana Rail Link, which was operating the train, were responding and investigating what the carriages were carrying, he added.
Photos posted on social media show some of the cars appearing to dip into the river.
The train carriages did not release any hazardous materials, Montana Rail Link said in a statement. The company said the cause of the derailment is being investigated.
The firm added: “We are committed to addressing any impacts to the area as a result of this accident, prioritising the safety of our employees and the public, and understanding the reasons for this incident.”
Montana’s US senators Steve Daines and Jon Tester said in separate tweets that they were monitoring the derailment and were in touch with local officials.
Federal regulators and members of US congress are urging the railways to do more to prevent derailments after recent fiery wrecks involving hazardous chemicals in Ohio and Minnesota prompted evacuations.
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