A man has been critically injured in a crash on the M1 in northern Sydney, with lane closures causing heavy delays.
The man was allegedly driving erratically about 4am on Friday when he crashed his vehicle into another car on the motorway at Berowra.
The 42-year-old man was treated at the scene by paramedics before being taken to hospital in a critical condition.
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The driver of the second car, a 30-year-old man, was taken to hospital with minor injuries.
“An investigation into the circumstances surrounding the crash has commenced,” police said.
Two of the three lanes on the motorway were closed for several hours but all lanes have now reopened.
Traffic remains heavy however and motorists have been advised to allow extra travel time.
