Emergency services confronted with 'chaotic' scene after multi-vehicle smash near Wollongong

Six people are in hospital and a major road remains closed after a multi-car crash north of the NSW city of Wollongong.

Five cars and a truck were caught up in the accident on Picton Road at Cataract just after midday today.

NSW Ambulance chief inspector Norm Rees said on arrival the crash scene was "chaotic" and spread over a long distance of more than 130 metres.

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"It appears the driver, a 44-year-old male, has veered onto the wrong side of the road due to a medical episode," Rees said.

"The truck has tried to avoid it, hitting the guard rail and then running back into traffic."

Rees said the 44-year-old was flown to Liverpool in a serious condition and his wife was taken to Liverpool Hospital.

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Four other patients were transported to Wollongong Hospital with various injuries due to the crash and exposure to the sun.

Police are investigating the circumstances surrounding the crash.

"Police urge everyone just to take care when they're driving through these school holidays," NSW acting inspector Owen Barnes

"Make sure you're paying attention, make sure you're not distracted and get to your destination safely."

Picton Road at Cataract was closed in both directions but has since re-opened.

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