A 47-year-old man has died following an incident on the A90 Peterhead to Fraserburgh road near St Fergus last week.
The driver had been travelling in a black Vauxhall Insignia which collided with a tree at around 6.20am on Thursday, July 26.
No other vehicles were involved.
The driver was taken to Aberdeen Royal Infirmary for treatment and has since died from his injuries.
Anyone with information is asked to call 101 quoting ref. no. 0606 of July 26.
Sergeant Scott Deans, from the Road Policing unit, said: “Our thoughts are with the family affected at this very sad time. One death on our roads is one too many and the heartbreak that is left behind is far-reaching.
“Enquiries are continuing and I would ask anyone with information to please get in touch. Likewise, dash-cam footage which captures the vehicle involved could be extremely useful to our investigations.”