A bus full of German teenagers has rolled over on an Italian highway, leaving 17 passengers injured.

Italian authorities from the civil protection office in the northern city of Trento said none of the passengers injured in the Sunday morning accident were in serious condition.

Thirty-five teens between 17 to 19 years old were headed home to Bremerhaven, Germany, from vacation when their vehicle ran off the road on the A22 Autostrada and ended up on its side.

Civil protection officials added that the teenagers that were not injured were taken to a local gym while those injured were treated in emergency rooms in local hospitals.

Italian authorities are still investigating the cause of the incident.

Almost two years ago, 39 people, out of 50 passengers on board a bus, were killed and around 10 others injured when the bus crashed in southern Italy.

All of the victims had been Italian holidaymakers returning from an excursion to the town of Telese Terme, famous for its hot sulfurous spas and a nearby lake.

In March, the European Union Commissioner for Transport Violeta Bulc published a report revealing a total of 25,700 road deaths across all 28 member states of the EU in 2014.

The report says almost 70 people die on the EU country's roads every day.