One person has been critically injured and choppered to hospital after a crash on a major West Auckland highway.
A section of State Highway 16 is closed and diversions are in place after a serious crash involving a single vehicle near Waimauku.
A motorist was trapped in their vehicle after it crashed into a tree around 1.20pm.
Police say the crash occurred past the Waimauku township heading towards Helensville.
An Auckland Rescue Helicopter Trust spokesman said a crew was called to assist shortly after the crash.
The driver was rescued from the car in a critical condition as an Auckland Westpac Rescue Helicopter crew landed on the scene, he said.
He was flown to Auckland City Hospital in the Westpac 1 helicopter.
Motorists were asked to avoid the area while the Serious Crash Unit examined the scene.
Police said this was expected to take some time, so members of the public should plan ahead of any travel plans this afternoon.
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