Motorcyclists were behind a grim spike in the national road toll on Saturday.
Four riders were killed in separate deadly crashes that all occurred within less than four hours.
One rider, a man in his 30s, died shortly after he was struck by a ute in the eastbound lane on Richmond Rd at Marsden Park in Sydney’s northwest about 3.30pm on Saturday.
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Passing drivers stopped and unsuccessfully tried to save the rider, as the ute driver fled.
Police launched a search for the alleged driver, a woman with a shaved head who was wearing white jeans and a blue singlet.
PolAir and a Police Dog Unit were involved in the search, as the major road was closed to traffic between Elara Blvd and St Marys Rd. It has since reopened.
The alleged hit-and-run driver has not yet been found.
Rider hit by truck Just over two hours earlier, another motorbike rider was killed in rural NSW about two hours south of Sydney.
The man in his 50s was struck by a truck carrying farm machinery on Oallan Ford Rd at Windellama.
Passers-by tried to help the man, but he could not be saved.
The truck driver was taken to Goulburn Hospital for mandatory testing.
Single-vehicle crash In Queensland, a 65-year-old man died in a single-vehicle motorbike crash in Ravenshoe, a rural town in the Tablelands Region, about 3.15pm on Saturday.
He was riding a black Triumph motorcycle on Wooroora Rd when he crashed and died.
Teen killed In South Australia, a teen rider was struck by station wagon on the winding roads of the Adelaide Hills about 2.40pm.
The 19-year-old Walkley Heights man was riding his Kawasaki motorcycle when he was hit by a Toyota station wagon on Gorge Rd and died.
The man and woman in the car were not injured.