Three women were in a critical condition after their car hit a stationary bus at BeverlyHills on Sunday.
About 6.25pm, emergency services were called to the M5, between Belmore Road and King Georges Road, following reports a car had crashed into a bus.
Police were told a Mazda travelling east on the M5 crashed into the back of a bus that was stationary in the breakdown area on the side of the road.
The young female driver, 19, and a female back passenger, 18, were trapped for a short time before being released by Fire & Rescue officers.
All four occupants, including a male front passenger, 18, and a female back passenger, 19, were treated at the scene by ambulance paramedics before two women were taken to Liverpool hospital and a man and a woman were taken to St George hospital.
The three women were in a critical condition and the man was in a serious but stable condition.
The bus driver wasn't injured and there were no passengers on board the bus at the time.
Campsie police officers, helped by officers attached to Bankstown Traffic & Highway Patrol, established a crime scene which was examined by specialist officers from the Metropolitan Crash Investigation Unit.
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