Three carriages on the train went off a truncated track near the town of Carnate, in Lombardy, at midday.
The only passenger travelling on the train reportedy broke a window to escape, and was given first aid at the scene before being transported to hospital as a precaution.
Public prosecutors opened a probe into the incident after regional railway Trenord said that “for reasons to be ascertained” the train left Paderno station “without any staff on board”.
The safety system then routed the train to a section of unused track at the Carnate-Usmate station, Trenord said in a statement.
Television footage showed one carriage leaning on its side and another at a 45° angle off the track.
