At least 13 female students were killed when 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 injured more than 40 people, Catalan Interior Minister Jordi Jane said at the accident site near Freginals.
There were 61 people on the bus, which was transporting international students participating in the EU's student exchange programme known as Erasmus back to Barcelona from a folk festival in Valencia.
Among the casualties were people from 19 different countries, the Catalan rescue services said. The bus was carrying students from a number of European countries, as well as Japan, the Palestinian Territories and New Zealand, among others.
Jane said later Sunday that forensic doctors would work through the night to identify the victims by using DNA from relatives.
"It's a sensitive issue," he said. "We will only release a list of the victims when all of the information has been confirmed with certainty."
The minister confirmed that all of the fatalities were women.
Twenty-three of the injured passengers remained in different hospitals late Sunday. Those who sustained light injuries are being questioned by the authorities. Jane was hopeful that they could help to identify the dead.
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, 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.