Four have died and a further 29 injured after a coach crash near Leipzig in Germany.
The Flixbus service was running between Berlin and Zurich. Police say the vehicle came off the autoroute without hitting any other on the road.
The reasons for the crash are still unknown.
The Swiss Federal Department of Foreign Affairs says it has no information if any Swiss nationals were on board.
The coach ended up on its side, but it had to be righted by rescue crews before all the occupants could be helped.
The service left Berlin at 8am yesterday and crashed only 170km into its 850km journey.
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