Victoria St is now closed between Queen and Hobson Sts.
Police are advising motorists to use alternate routes as road closures may be in place for some time.
An officer at the scene told delivery drivers the road was expected to be closed for the next four hours.
A red car involved in the crash has been left crumpled.
The roof of the crashed vehicle has been removed by emergency services to extract those inside.
A large cordon is now in place around the blocks close to the Sky Tower, with pedestrians being kept well back.
One of the vehicles involved in the collision is a police car.
The patrol car remains on the city street with damage to the front of the vehicle.
Police investigate an early morning crash on Victoria St West involving a police car and another vehicle.
A person who lives on Victoria St said that he saw the red car “flying past” and swerving, being followed closely by a police car.
He said the red car crashed before the police car also crashed.
The resident said he saw a second police car waiting at the Albert St intersection.
A worker nearby said they heard a “big bang” and ran outside and saw the crash. “It looks really bad.”
The Serious Crash Unit is on the scene, attempting to determine the cause of the crash.
A series of markers have been placed on the street near the Federal St intersection leading down towards the crashed vehicles.
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