Travellers on an intercity train in Austria were startled when a recording of an Adolf Hitler speech was played on board.
Instead of the normal announcements, a crowd could also be heard shouting “Heil Hitler” and “Sieg Heil” over the train’s speaker system.
The operator said there had been several such incidents in recent days.
One passenger on the Bregenz-Vienna service told the BBC that everyone on the train was “completely shocked”.
In a statement sent to the BBC, Austrian Federal Railways (ÖBB) said: “We clearly distance ourselves from the content.
“We can currently assume that the announcements were made by people directly on the train via intercoms. We have reported the matter to the police,” the ÖBB said.
It is understood that complaints have been filed against two people.
Hitler was born in Austria and emigrated to Germany in 1913 as a young man.