A 25-year-old man is in custody after he allegedly fled the scene of a fatal crash on the M1 at Mount White on Friday afternoon.
One man died and another man was injured when two utes and a pantech Coles truck collided about 4.45pm on Friday, causing traffic chaos for drivers heading out of Sydney.
Police originally thought only the truck and the ute were involved in the crash but they now say a third vehicle - another ute - played a role.
Paramedics arrived to find two people trapped in vehicles on the highway north of Sydney.
Photo: Nine News"The driver of the second utility is alleged to have left the scene," NSW Police said.
"Following further inquiries by crash investigators, a 25-year-old man was arrested at a Wyong address."
A 46-year-old man died in the crash. Police are preparing a report for the coroner.
One man died at the scene. The truck driver has been taken to hospital for mandatory blood and alcohol tests.
Photo: Nine NewsThe truck driver was not seriously injured. He was taken to hospital where he underwent mandatory blood and urine tests.
The 25-year-old man was charged with dangerous driving occasioning death, negligent driving occasioning death, failing to stop and render assistance causing death, and not giving particulars to police.
He was refused bail when he appeared in Wyong Local Court on Saturday morning. He will reappear in Gosford Local Court on Monday.
"Inquiries into events leading up to the crash are still continuing," police said.
The crash caused "extensive delays", with traffic backing up for several kilometres.
Anyone with more information is urged to call Crime Stoppers on 1800 300 000.
Esther Han is a health reporter at The Sydney Morning Herald and The Sun-Herald. Before that, she spent three years as Fairfax Media's consumer affairs editor. She has also covered food and wine.
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