Police are appealing for witnesses after a man was seriously injured in a multi-vehicle crash in Luddenham.
About 5.20pm Monday, officers from Nepean Police Area Command were called to The Northern Road, Luddenham, after reports of a crash.
Police have been told a white Volkswagen Caddy travelling south collided with the rear of a blue Toyota Hilux utility, forcing the Hilux onto the wrong side of the road and into a Volvo tipper truck travelling northbound.
The Hilux also impacted with a green Ford Falcon which sustained minor damage in the crash, before catching fire and trapping the 32-year-old male driver inside.
He was freed by bystanders and treated at the scene by NSW Ambulance paramedics for serious internal injuries, then taken to Westmead Hospital where he remains in a critical condition.
The driver of the Volkswagen, a 17-year-old boy who is a P1 provisional licence holder, was taken to Nepean Hospital where he underwent numerous scans and treatment for non life-threatening injuries.
Meanwhile, the driver of the Ford, a 40-year-old man, and the driver of the truck, a 26-year-old man, were arrested and taken to Nepean Hospital for mandatory testing.
A passenger in the Ford, a woman aged 64, was uninjured.
Officers from Nepean Police Area Command established a crime scene and specialist investigators from the Metropolitan Crash Investigation Unit have commenced an investigation into the circumstances surrounding the crash.
Investigators are appealing for anyone who witnessed the crash, or has dashcam footage from the area at the time, to contact police.
Anyone with information about this incident is urged to contact Crime Stoppers 1800 333 000.