The coach was carrying at least 40 passengers at the time.
Thirteen passengers were taken to Wagga Wagga and Albury hospitals with a range of injuries, including three with serious but not life-threatening injuries.
Among those injured were two women in their late teens with leg injuries, and a woman in her 20s with head and leg injuries. One man is suspected to have a broken leg, a NSW Ambulance spokesman said.
A further 29 passengers were taken to hospital for assessment, a Murrumbidgee Local Health District spokeswoman said.
The driver of the truck, which was described by police as a “heavy vehicle”, was uninjured and taken to Wagga Wagga Base Hospital for mandatory testing.
The highway was closed northbound, with a diversion between Little Billabong Road and Tumbarumba Road. A crime scene was established. Anyone with dash cam footage is urged to contact Crime Stoppers on 1800 333 000.
Meanwhile, a man believed to be in his 40s died after being found unconscious and seriously injured next to the Great Western Highway in Leura, in the Blue Mountains. Police said he may have been struck by a car.
A 50-year-old man attended Katoomba police station and was taken to hospital for mandatory testing. Investigators are seeking information about a man seen walking along the road before 11pm on Friday.
Double demerit points apply in NSW from 12.01am on December 20 to 11.59pm on January 1 for offences including speeding and mobile phones.
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