By Georgina Mitchell and Matt O'Sullivan
Five people have been taken to hospital after a ferry crashed into a pier at Circular Quay, leaving 18 people injured, one seriously.
Multiple ambulances were called to the scene after the crash, which happened at around 4.15pm on Tuesday.
It is understood the supercat smashed into a wooden backboard on one of the piers at Circular Quay after it got into trouble reversing.
A NSW Ambulance spokesman said 18 people were assessed by paramedics after they fell during the crash.
The scene at Circular Quay on Tuesday afternoon.Credit: Nine News
Most had minor injuries, but one patient is believed to have spinal injuries.
Helicopter footage from the scene showed one man being carried off the ferry on a spinal board by officers from Police Rescue, as he breathed in from a green pain relief whistle.
One woman, interviewed by news crews as she was pushed in a wheelchair, said she was hurt "straight across the chest".
Another, an American tourist being pushed on an ambulance stretcher, said the ferry came to "a huge, abrupt stop".
A passenger is carried from the ferry on a spinal board.Credit: Nine News
"It's like we hit something and I went flying forward," she said. "Hit my chest against a steel bar, knocked back, someone fell on me."
A third passenger said she banged her hip and was left with minor injuries, but saw others who had broken skin and were holding their arms.
Three patients were taken by ambulance to Sydney Hospital on nearby Macquarie Street, while another two were transported to St Vincent's Hospital.
The ferry involved was operating the 3.45pm Watsons Bay to Circular Quay service. Nine News reported the ferry made a previous stop at Garden Island as normal.
However, passengers said when it arrived at Circular Quay, it didn't slow down.
Police said the catamaran "impacted with a barrier", throwing passengers to the ground. It is not known how fast it was travelling at the time of impact.
Transport for NSW confirmed that the Supercat came into contact with the far eastern pontoon at Circular Quay Wharf as it was berthing.
The incident is being investigated by the Office of Transport Safety Investigations (OTSI).
"Transport for NSW is working with Sydney Ferries operator Harbour City Ferries and will fully cooperate with OTSI to identify the cause of the incident," a Transport for NSW spokesperson said.
The catamaran will be moved to Harbour City Ferries' maintenance facility at Balmain.
Two ferry services were cancelled following the crash: the 5.45pm Circular Quay to Taronga Zoo service, and the 6.01pm Taronga Zoo to Circular Quay ferry.
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