Police have said that at approximately 6.10pm on December 24, a black Peugeot 3008 collided with a road barrier and sign at the side of the A34 northbound near to the A303 slip road.
The driver, a man in his 60s, was pronounced dead at the scene.
His next of kin have been informed and are being supported by specialist officers.
In an appeal, Hampshire Constabulary said: ‘Did you see what happened? Do you have dash cam footage showing the collision or the moments beforehand?
‘Please contact us on 101 or report online, quoting reference number 44210514505.’
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