A Polish tourist bus crashed into a ditch on a Hungarian highway in the early hours of Sunday, killing 12 people and injuring 10 others, five of them critically.
The bus, with 57 passengers and two drivers, was reportedly transporting pilgrims from Serbia back to Poland.
11 people were declared dead at the scene and another person died in hospital, Hungary's national disaster agency said. The ambulance service said 37 people suffered minor injuries and were taken to hospitals in four cities. The highway was closed for several hours.
Hungary's Interior Minister Gabor Posfai said the driver had been detained and media quoted police as saying he had fallen asleep at the wheel when the bus crashed at 1 am on the M3 highway near Mezokeresztes, about 140 kilometres from Budapest.
A special flight with medical and consular aid was sent from Poland, the country's Prime Minister Donald Tusk said.
In a social media post, Hungarian Prime Minister Péter Magyar offered his condolences to the families of the victims and wished the injured a swift recovery. He also thanked those taking part in the rescue operation for their work.
It was the worst road accident in Hungary since a train hit a German tourist bus at Siofok in 2003, killing 33 people. In 2002, a bus carrying Polish pilgrims crashed near the western town of Balatonszentgyorgy, leaving 19 people dead.
