Part of the road between Pulham St Mary and Starston was closed on Saturday evening after a crash.
The incident happened at 7.55pm on The Street.
South Norfolk councillor Clayton Hudson said the crash involved one vehicle which is believed to have hit a tree.
He said: 'My wife was in the garden letting the dogs out and she heard it. A couple of other people also heard it.
'Myself and a couple of parish councillors, who are also farmers, helped to stop the traffic until the firefighters from Harleston turned up.'
Mr Hudson said he believed the driver had fled the scene.
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