UPDATE: NSW Police have established a crime scene following a fatal crash between a truck and car in Thirroul on Friday, 16 February.
They have confirmed that four people were involved in the accident.
NSW Fire and Rescue worked to free a woman from the car before she was treated at the scene by NSW Ambulance paramedics and flown to hospital in a critical condition.
Two male occupants of the truck were also treated at the scene by paramedics before they were flown to hospital in a critical condition.
A fourth person, believed to be a man, died at the scene, who is yet to be formally identified.
A report will be prepared for the information of the Coroner.
Officers attached to Wollongong Police District have established a crime scene which will be forensically examined by specialist police from the Crash Investigation Unit.
Anyone with information into the incident or dashcam footage is urged to call police or Crime Stoppers on 1800 333 000.
EARLIER: A man has died after a crash involving a truck and a car at the bottom of Bulli Pass at 1:50 pm Friday, 16 February, a NSW Police spokesperson said.
It is believed the deceased was found underneath the truck. It is not yet understood how he came to be under the truck.
A NSW Ambulance spokesperson said there were nine ambulance crews on the scene and three rescue helicopters treating at least three additional patients.
Their conditions, ages and genders cannot be confirmed at this stage.
The accident, near the intersection of the Princes Highway and Lawrence Hargrave Drive, has caused significant traffic ongoing traffic delays.
Motorists are advised to avoid the area if at all possible. Emergency services and Transport for NSW crews are attending.