ONLY an hour after a semi-trailer car carrier lost its tail shaft and 18 cars were damages after running over it, a woman died on the same road.
Crash investigators are today still looking into the cause of the fatality on the F3 at Berowra.
Emergency services had been on the scene of the multi-vehicle incident north of Sydney last night.
A southbound semi-trailer car carrier had lost its tail shaft about 2km south of the Hawkesbury River Bridge around 9.15pm.
Running over the tail shaft, 18 cars were damaged and fuel was spilled across the roadway.
Police from Kuring-Gai and Brisbane Water Local Area Commands and Traffic Highway Patrol Command, NSW Ambulance Paramedics, Fire and Rescue NSW and Rural Fire service units as well as maritime services crews were on scene quickly.
No one was injured but lanes one and two of the freeway were closed as the damaged cars and truck was cleared.
Then about 10.30pm a woman, 64, died following a crash involving a Rural Fire truck, which had been at the earlier crash and two cars.
The fire truck, Toyota Corolla and Mazda 3 collided in the northbound lanes of the F3 at Berowra.
NSW police say the woman was found deceased on the roadway.
It is believed she was ejected from the Toyota Corolla during the collision before being run over by another vehicle.
The driver of the Toyota, a 76-year-old man, was cut free from the wreckage and taken to Royal North Shore Hospital for treatment of head, internal and suspected spinal injuries.
He was believed to be in a critical condition this morning.
The driver of the fire truck, a 33-year-old man and the driver of the Mazda 3, a 24-year-old woman, were taken to Hornsby Hospital for treatment of minor injuries.
All three motorists will undergo mandatory drug and alcohol testing.
Inquiries into the cause of the collision are being undertaken by officers attached to the Metropolitan Crash Investigation Unit.
The F3 has been completely cleared in both directions and traffic is again flowing freely.
Investigators are appealing for anyone who witnessed the crash or circumstances leading up to it to come forward.
Anyone with information about this incident should call the Metropolitan Crash Investigation Unit or Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page: https://www1.police.nsw.gov.au/. Information you provide will be treated in the strictest of confidence. We remind people they should not report crime information via our Facebook and Twitter pages.