Three cars collided on Picton Road at Wilton around 12pm on Saturday, November 11.
The accident occurred near the Hume Motorway on the east-bound side of the road.
One man in his 60s was trapped in his car.
Paramedics treated nine other people at the scene.
Both eastbound lanes were blocked before they re-opened around 2pm.
Traffic was backed up to the Hume Motorway.
Ten people were transported to hospital. The man in his 60s was taken to Liverpool hospital in a serious but stable condition.
A woman in her 60s with neck injuries was taken to Wollongong in a serious but stable condition.
A woman in her 40s with injuries to her abdomen was taken to Wollongong in a stable condition.
A child under 10 with no injuries was taken to Wollongong in a stable condition.
A man and a woman - both in their 40s - with four teenage children were taken to Campbelltown Hospital with minor injuries in a stable condition.
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