Three road workers have been taken to hospital after a semi-trailer crashed into their work zone on a NSW highway and burst into flames.
The accident happened on the southbound lanes of the M1 motorway at Kangy Angy in the Central Coast region in the early hours of Tuesday, and immediately closed the southbound lanes of the highway.
The B-Double truck crashed through a work zone then hit a slow-moving Hino truck, NSW Police said in a statement.
The Hino truck flipped and hit a second stationary truck that then hit a road worker.
The 43-year-old male Hino driver suffered serious injuries. He was taken to John Hunter Hospital along with an injured road worker, a man aged 58. They remain in a stable condition.
A female road worker took evasive action and avoided injury. She was taken to Wyong Hospital suffering shock and has since been released.
Paramedic specialist Andrew Craig described the firey scene.
"When you look at the scene and the carnage, it's incredibly lucky there were no fatalities," he said.
"When you're called to an accident involving a truck and road workers, you immediately prepare for the worst.
"This is a timely reminder that things can change in an instant on the road and drivers should remain aware of road workers and drive to the conditions."
The 62-year-old semi-trailer driver was able to free himself and escaped injury.
He was taken to hospital for mandatory tests.
Traffic was still very heavy in both directions on the M1 Pacific Motorway on Tuesday morning, and motorists were advised to allow for extra travel time.
Craig Moran, Transport for NSW Executive Director Customer Journey Management, told reporters he doesn't expect major delays to continue on Tuesday afternoon.
He warned motorists need to drive to conditions on the southbound lanes because the truck still needs to be cleared from the road.