The driver of a tour bus which crashed and caught fire in Taiwan killing dozens of Chinese tourists was drunk when the accident happened, investigators said Friday.

In the worst road accident ever to hit mainland visitors to the island, an entire tour group of 24 died when their bus was engulfed in flames and rammed through an expressway barrier last week.

Tests on the remains of the driver — who died in the crash, alongside a local tour guide — found an alcohol concentration of 1.075 milligrams per litre of breath, prosecutors said in a statement.

taiwan bus
Photo: Weibo.

That put the Taiwanese driver, who was identified only by his surname Su, at more than four times the legal limit of 0.25 mg per litre.

“He was drunk driving — a very severe case of drunk driving,” said chief investigator Wang Yi-wen.

The discovery means the probe will now focus more on the driver’s mental and physical state, he added.

Investigators are delving into Su’s habits, diet, and social circle to determine why he might have been driving over the limit, Wang told AFP.

Tests did not find any traces of drugs or sedatives in his system, the statement from prosecutors said.

Investigators have already said that five bottles of gasoline were found in the bus, despite regulations banning inflammable substances in a vehicle.

They have searched his home twice and questioned his relatives and co-workers.

Local media said Su, the main breadwinner in his family, struggled financially and interacted little with his colleagues.

taiwan bus crash
Photo: Screenshot from video.

The bus carrying the tourists from China’s northeastern city Dalian was heading to Taipei’s main Taoyuan airport on Tuesday last week after the group had completed an eight-day trip around the island.

Distraught relatives who came to Taiwan to identify the bodies of the victims questioned why none of them were able to escape through the emergency exits when the fire ripped through the bus.

One eyewitness said trapped passengers inside the bus had been pounding on the windows as it careered off the road.

Chinese officials have demanded Taiwan take measures to ensure the safety of mainland visitors to the island.

Taiwan saw a boom in tourism from China under previous president Ma Ying-jeou, who oversaw an unprecedented eight-year rapprochement with the Beijing.

But numbers have slipped since Beijing-sceptic Tsai Ing-wen won a landslide victory in elections in January.

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