The Col des Nuages derailment was a train derailment that occurred in eastern French Indochina, in modern-day Vietnam, on 24 June 1953, during the First Indochina War.
Railway officials announced the day after that "about 100 or more" were killed when a passenger train plunged 50 feet through a sabotaged viaduct.
The pass had frequently been the scene of attacks by the communist-directed Viet Minh rebels.
Officials said that a strong explosive charge detonated just as the train arrived at the viaduct, tumbling a 25-foot span into the ravine.
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