A woman died and at least two people suffered life-threatening injuries after the charter coach, travelling from Cairns to Airlie Beach, rolled off the Bruce Highway near Gumlu in Queensland's Whitsundays.
There were 29 people on the FlixBus coach when it crashed about 4pm on Thursday, including the driver, a 70-year-old Mackay man who was taken to hospital with minor injuries.
All of the passengers on board were tourists, many of them foreign nationals.
Queensland Premier David Crisafulli said it was a tragedy that would be felt for a long time to come.
"Someone in the prime of their life, on the trip of a lifetime, in another country, has lost their life," he told ABC News on Friday.
"You've got young people in many cases living out their dream in a foreign country and to have something like this happen, I can only imagine what that feels like for the parents and families, in many cases, on the other side of the globe."
Superintendent Dean Cavanagh from Mackay Whitsunday Police said members of the public had provided police with "direct evidence" and dashcam footage of the incident.
He would not speculate about the cause of the crash, saying the forensic crash unit would investigate what he described as a very complex incident in an isolated area.
He confirmed a bus operated by the same company was involved in a similar incident near Mackay earlier this year.
"There was an incident involving a similar bus in February, just south of Mackay, where the bus left the roadway, ran into a barbed wire fence and the 55-year-old female driver at the time was issued a traffic infringement notice as a result," Supt Cavanagh told reporters on Friday.
Twenty-eight people were taken to hospital after Thursday's crash, including two in life-threatening conditions who were transported to Townsville University Hospital.
Others were taken to Townsville, Ayr and Bowen hospitals by ambulance, private bus and plane in a stable condition.
Eleven ambulances, two helicopters and a Royal Flying Doctor Service plane attended the scene.
No other vehicles are believed to have been involved in the incident.
Thursday's crash occurred near the site of a collision involving a Greyhound bus that killed three passengers and seriously injured others in June 2024.
Queensland Transport Minister Brent Mickelberg said the incident underlined the need for upgrades to the highway.
"It's why we've fought so hard to get an 80/20 funding deal with the federal government and $9 billion of investment on the Bruce Highway to make it safer," he told reporters on the Gold Coast.
"All of that money is being spent north of Gympie and south of Cairns on stretches of road like the one the tragic incident occurred on yesterday."
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