Rail authorities in Italy have had to take emergency action after a driverless train's engine hurtled nearly 200 kilometres through the countryside at 80 kilometres an hour.

The driver had set the engine in motion, leaned out to see if the line ahead was clear, then slipped and fell from his cabin.

The locomotive automatically gathered speed up to 80 kilometres an hour.

Stations along the line were evacuated as the engine smashed its way through heavy obstacles piled on the track in an attempt to stop it.

It was finally switched on to a track to a remote disused station, where it came off the rails.