A Gold Coast man has had surgery in an attempt to save his arm after a bus shelter collapsed on top of him during a freak accident.

The 42-year-old man was waiting at the brick shelter on Township Drive in Burleigh Heads just before 5pm on Monday when a bus hit the structure.

The impact caused one of the shelter’s walls and its roof to collapse.

Police and ambulance officers were called to the scene and found the man with potentially life-threatening injuries to his arm and chest.

He was taken to Gold Coast University Hospital in a serious condition and underwent surgery overnight.

The ABC understands the surgery was designed to save the man’s arm.

A Queensland Health spokesperson said the man remained in a critical condition.

The Forensic Crash Unit is investigating the cause of the crash, and police are asking witnesses or anyone with relevant dash-cam vision to contact them.

A spokesperson for the Transport Workers Union said it was aware of the incident and it was offering support to its members.

“The TWU passes on our deepest thoughts for the injured pedestrian and his family,” the spokesperson said.

“While we understand there was another vehicle involved, potentially blocking usual access to the bus stop, this is being investigated by Queensland Police and we will refrain from further comment.”

In a statement, bus operator Kinetic said no passengers were on board at the time of the incident.

“We have commenced our own investigation into how this occurred, and we are cooperating fully with authorities,” the statement said.