POLICE are investigating a fatal crash near Bathurst, on NSW's Central West on Saturday.
About 1.40pm, a westbound Toyota Corolla and an eastbound Mitsubishi Triton collided on the Great Western Hwy at Glanmire, 9km from Bathurst.
Following the initial impact, an eastbound semi-trailer collided with the Mitsubishi utility.
The three occupants of the Corolla - the male driver and his wife, both aged 73, and a 95-year-old woman - died at the scene.
All three were from Kelso.
The 33-year-old male passenger of the utility, from Orange, also died at the scene.
The driver, a 38-year-old Orange man, was airlifted to Westmead Hospital where he remains in a critical condition.
The truck driver, a 53-year-old Stanhope Gardens man, was not injured but was taken to hospital for treatment of shock and to undergo mandatory blood and urine testing.
Two greyhounds were being carried in the rear trailer of the Mitsubishi. One of the dogs died at the scene while the other escaped and has not yet been located.
An investigation into the circumstances surrounding the crash, and the events leading up to it, is being led by the Chifley Crash Investigation Unit.
Investigators are appealing for anyone who witnessed the incident, or the events leading up to it, to contact Chifley Police or Crime Stoppers on 1800 333 000.