At least 16 people are dead after a bus crash on Indonesia’s main island of Java.

The bus carrying 34 people lost control on a toll road and struck a concrete barrier before rolling onto its side in the early hours of Monday, said Budiono, a search and rescue agency chief.

The inter-province bus was travelling from Jakarta to Yogyakarta, an ancient royal city and the cultural heart of Java, when it overturned while entering a curved exit ramp at the Krapyak tollway in central Java’s Semarang city, he said.

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Known for its temples and historical sites, Yogyakarta is a popular tourist destination.

The authorities have not yet released any information about the nationalities of those killed and injured.

“The forceful impact threw several passengers and left them trapped against the bus body,” Budiono said.

Police and rescue teams arrived about 40 minutes after the accident and recovered the bodies of six passengers who died at the scene.

Another 10 people died on the way to a hospital or while being treated, Budiono said.

The 18 victims being treated at two nearby hospitals included five people in critical condition and 13 in serious condition.

Television news reports showed the yellow bus overturned on its side and surrounded by National Search and Rescue Agency personnel and police as ambulances transported victims and the dead away from the accident scene.