At least 13 students were killed as a packed tour bus overturned and crashed into another vehicle on a highway in north-eastern Spain, the Catalan government said Sunday.
The accident, which took place near the port city of Tarragona, also severely injured about 30 people, Catalan Interior Minister Jordi Jane said at the accident site near Freginals.
Another 13 passengers suffered minor injuries.
There were 57 people on the bus, which was transporting international students that were part of the EU's student exchange programme known as Erasmus back to Barcelona from a folk festival in Valencia.
It wasn't clear which countries the victims were from.
"We can't rule out that there were Germans in the bus," a spokeswoman for the German Foreign Ministry told dpa.
Broadcaster TV3 reported that the driver lost control of the bus. It then crashed through a median, overturned and collided with a vehicle in the opposite lane.
The excursion organizer chartered five buses back from the festival. The bus involved in the crash was the last of the five, TV3 reported.
The crash appeared to be due to human error by the driver, minister Jane said.
The driver of the bus survived the crash with minor injuries and tested negative for drugs and alcohol, judicial authorities in Barcelona said.