It's said to have happened Wednesday 6th February in Whipton Village.
It's alleged a man who was driving a white Skoda Fabia on Vaughan Road at around 2.30pm, stopped his car in the middle of the road, approached a female pedestrian and began to verbally harass her.
It's believed another motorist stopped to intervene - the man then went back to his car and drove off.
The woman was left shaken but physically unharmed.
Officers would like to speak to anyone who was in the area during the time of the incident, and would especially like to locate the person who intervened.
Anyone with any information is asked to email 101@dc.police.uk quoting crime reference CR/011470/19.
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