Peak hour traffic was affected following a three car pile up, including a Police Highway Patrol car, at the intersection of Hawkesbury Valley Way and Macquarie Street Windsor this morning.
Emergency services responded to reports of the smash, which occurred at about 8.30am.
On arrival they have come across three vehicles that had been involved in the crash, including a police car which had extensive damage to the rear of the vehicle.
A Toyota Land Cruiser has extensive damage to the front of the vehicle and Toyota sedan also had damage to its front bumper.
Traffic in both directions was seriously affected as crews cleared the roadway.
No one was transported to Hospital with two people suffering only minor injuries. Police are investigating.