British and Irish exchange students are feared to have been injured in a coach crash which killed 13 women.
The bus, carrying 57 passengers, was returning from Spain's largest fireworks festival when it crashed on a highway, killing 13 and injuring around 30.
One of the wounded is in a critical condition in hospital, according to Catalonia's president Carles Puigdemont.
The students, all female, were from various countries taking part in an Erasmus exchange programme at university in Barcelona.
A number of passengers were from the UK and Ireland, according to the Catalan government.
Spanish interior minister Jorge Fernandez Diaz confirmed the death toll was 13 and said 28 passengers received medical treatment in local hospitals while others were treated at the scene.
They were on their way back from the renowned Fallas fireworks festival in Valencia when the coach hit the barriers of the AP7 highway near Freginals, halfway between Valencia and Barcelona.
Television images from state broadcaster TVE showed the bus also crashed into an oncoming car on the opposite side of the highway.
The bus driver was being held at a police station in the city of Tortosa, according to Jordi Jane, spokesman for Spain's north-eastern Catalonia province.
Mr Diaz said the driver passed alcohol and drug tests he was given.
Ireland's Department of Foreign Affairs and Trade said two Irish students were injured in the crash.
"We can confirm that two Irish people received non-life threatening injuries in this morning's bus crash in Tarragona, Spain," a spokesman said.
"We stand ready to provide consular assistance."