A 22-year-old woman was taken to hospital where she is in a critical condition after a crash.
The collision involved a white Audi A3 near to the Quoybraw junction on the B876 in Wick at around 4.15am on Saturday.
Emergency services attended and the woman was taken to the Aberdeen Royal Infirmary.
Staff describe her condition as critical.
Sergeant Christopher Donaldson, from the Divisional Road Policing Unit based at Dingwall, said: “Our investigation into the cause of the crash is continuing.
“I would urge anyone who seen this car driving on the road, or who has any information that may assist us to please contact us. I am also keen to obtain any dash-cam footage that may help our inquiry.
“Anyone with information is asked to contact officers through 101 quoting reference number 0741 of August 5.”
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