A man was punched in the face in a shocking attack that was witnessed by a dog walker. 

The assault happened in The Backs in Chesham last month. 

Police say the victim, a white male, was punched in the face by another man at around 5.45pm on March 7. 

The shocking attack was reportedly witnessed by a person who was walking a dog with golden hair. 

Police want to hear from anyone who may have information about the assault and have urged people to come forward if they can help. 

If you think you can help the investigation, call 101 quoting crime reference number 43220156454. 

The officer in charge of the investigation is PS 3675 Darren Walsh, based at Amersham Police Station.