Emergency services are working to free trapped passengers following a horror smash on Sydney's northern beaches.
A truck has ploughed into cars at the corner of Pittwater and Warringah Roads at Dee Why, around 6.10am.
According to witnesses, the truck driver was driving down Warringah Rd and turned left on Pittwater Road. It then hit the median strip and crossed the road before overturning.
There are seven injured in the accident, including the driver of the truck.
Police and ambulance workers at the scene of the crash. Photo: 7News
There were two people seriously trapped under the crash. 7News understands the 29-year-old driver of a ute has managed to free himself from under a vehicle.
He is being transferred to hospital.
A female driver of another car has also been freed. She has been treated by ambulance officers and will be transferred by helicopter to Royal North Shore Hospital.
The driver will undertake mandatory blood and alcohol testing.
The accident is similar to one in 2000 where a truck crashed into the back of a car killing a baby boy.
In that crash, a truck crashed into nine cars that were waiting at lights on Warringah Rd.
The 11-month-old boy was rescued from the car however later died from burns.
There is leaking fuel however it is contained and there is no danger. Motorists are being told to avoid the area and to expect extensive delays.
The scene of the crash on Pittwater Rd, Dee Why. Photo: 7News