MADRID (AP) – A bus carrying university students back from Spain’s largest fireworks festival crashed Sunday on a main highway in northeastern Spain, killing 13 passengers and injuring 30 others, the country’s interior minister said.

Initially, regional government spokesman Jordi Jane said 14 had died in the crash but Minister Jorge Fernandez Diaz later confirmed the death toll was 13. He said 28 passengers received medical treatment in local hospitals and others received first aid at the crash site.

The bus, which was carrying 57 passengers, appeared to have hit the right-hand side barriers of the AP7 highway before cartwheeling across the road and slamming into the central fence, landing on its side, said Jane, spokesman for Spain’s northeastern Catalonia province.

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, Jane said. Road conditions were good at the time of the crash and investigators were looking into the cause of the accident, he said.

Fernandez Diaz said the driver passed alcohol and drug tests he was given.

Jane said emergency rescue workers were working to clear the wreckage that had closed the major highway linking Spain with France along the Mediterranean coast in both directions. The crash took place near Freginals, halfway between Valencia and Barcelona.

Jane said the students – part of the Erasmus exchange program – had traveled to Valencia to take part in the renowned Fallas fireworks festival and were returning when the bus crashed. The minister said students were of several nationalities, including Spanish. Jane said most were studying at two universities in Barcelona.

The Erasmus program provides foreign exchange courses for students from counties within the 28-nation European Union and enables them to attend many of the continent’s best universities.

The Fallas festival is held each year in eastern Valencia on the feast day of St. Joseph and draws thousands of tourists from across the world.

Large wooden monuments and effigies representing famous people often in humorous postures that local workshops take a year to build are burned in a colorful ceremony accompanied by a cacophonous barrage of very noisy fireworks.