A Hampshire police spokesman said: "The road is expected to remain closed for the rest of the day while collision investigators examine the scene and arrange for the vehicle to be recovered."
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The decision was met with outrage and anger by UK cities which were on the shortlist for the prestigious award.
Mr Lewis is one of a number of Labour and Tory MPs under investigation by party officials over allegations of inappropriate conduct.
A jury has failed to reach a verdict in Emile Cilliers' trial on charges of attempting to murder his wife by tampering with her parachute.