A motorcyclist has died after he was struck twice on a major motorway.
The man was hit near the M4 at Merrylands, by the Burnett Rd on-ramp, in Western Sydney about 2am on Wednesday.
The rider was knocked from his motorcycle by a white sedan and then hit by a second vehicle, which was a police car.
The man was critically injured and paramedics began CPR before the rider was taken to Westmead Hospital fighting for life.
He could not be revived, and is yet to be formally identified, NSW Police said.
The driver of the white sedan, and the male senior constable involved in the crash, were also taken to Westmead Hospital for mandatory testing.
The police officer involved was not on urgent duty at the time of the crash, and did not have lights or sirens activated at the time.
“There had been no interaction with, and no pursuit of, the motorcyclist or any other vehicle,” police said.
The officers were returning to a police station when the incident occurred.
The investigation will be the subject of an independent review by the Professional Standards Command and oversight by the Law Enforcement Conduct Commission.
The M4 is closed to eastbound traffic as emergency services work at the scene, and there is no forecast of when the road will reopen.
Light vehicles are being diverted on the Cumberland Hwy, Great Western Hwy and Burnett St to return to the M4 Mwy, according to LiveTraffic NSW.
Heavy vehicles are being diverted on the Cumberland Hwy, Great Western Hwy, Church St, Parramatta Rd and James Ruse Dr to return to M4 Mwy.