Police are investigating the circumstances surrounding a fatal collision near Menangle, south-west of Sydney .
About 11.25am today (Tuesday 24 January 2012), emergency services were called to the northbound lanes of the Hume Highway following a crash between a truck and a car.
The three occupants of the car have been confirmed as deceased and reports will be prepared for the Coroner.
The male truck driver sustained minor injuries and has been taken to Campbelltown Hospital for treatment. He will also be subjected to mandatory blood and urine testing.
Anyone who witnessed the collision or the events leading up to it, is asked to contact Crime Stoppers on 1800 333 000.
The Hume Highway has been closed at the Menangle Bridge and northbound traffic is being diverted onto Picton Road.
Motorists are asked to avoid the area and taken alternate routes until further notice.
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