At least four people were killed and about 30 injured when a train derailed in Germany's south-eastern state of Bavaria, police say.

The train, which was carrying many students, was heading to Munich when three carriages came off the tracks near Garmisch-Partenkirchen.

It is unclear what caused the accident, a police spokesperson said.

Images published by local media show several crumpled train carriages lying on their sides.

An official from the Garmisch-Partenkirchen local authority had initially suggested that some 60 people had been injured, but Stefan Sonntag, a spokesperson for the German federal police, said that figure referred to the number of passengers on the train.

In a separate development, a carriage on an Italian high-speed train travelling from Turin to Rome derailed while approaching the capital.

Local emergency officials say nobody was injured in the incident, which saw the train's back carriage come off the tracks as it neared the Serenissima tunnel in Rome.

In Germany, Mr Sonntag told reporters that 15 of the injured were in serious condition at a local hospital.

Officials said that people had been "pulled through the windows" to rescue them from the crash.

Earlier, police said that it could not be ruled out that a number of students celebrating the beginning of the summer holidays are among those injured, but Mr Sonntag said it was too early to offer any comment on such reports.

A US soldier based at a nearby air base was driving past when the train derailed. He told local media the accident had been "just awful - suddenly the train overturned".

Six helicopters, including three scrambled from the Austrian region of Tyrol, were sent to the scene to assist in rescue efforts.

The accident happened at around 13:15 local time (11:15 GMT) on Friday, shortly after the train left Garmisch-Partenkirchen for Munich.

It comes as Germany launched a new discounted rail ticket and Mr Sonntag said the regional train was “very crowded and many people were using it, hence the high number of injured”.

Part of the route between Munich and Garmisch-Partenkirchen has been blocked off and traffic has been diverted, German rail operator Deutsche Bahn says.

Germany’s deadliest rail crash in modern times occurred in 1998 when a high-speed train derailed in Eschede in Lower Saxony, killing 101 people.

The country’s most recent fatal crash took place in February, when one person was killed and 14 others were injured in a collision between two trains near Munich. (BBC)

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