A 37-year-old was assaulted in Masterton McDonald's carpark on Monday night after an altercation with a stranger.
Senior Sergeant Carolyn Watson said the man was approached by a man he did not know while he was sitting in his car, and the pair had an altercation after the driver got out of the car.
As he was stepping back into the car, the man punched him in the right side of face and then ran down Lincoln Rd and into Queen St, said Ms Watson.
She said the assaulted man went to A&E, but was not thought to be badly hurt.
Police were looking for a light-skinned Maori of short, slim build, with light-brown hair in a ponytail, and wearing a light-coloured top and dark trousers, and was drinking from a cask wine bladder.
Earlier this month an 18-year-old woman was punched in the face at the carpark, and in May a teen's jaw was broken in an assault.
A McDonald's spokeswoman said safety was of the utmost importance to the company, and security staff were in place on Friday and Saturdays from 11pm to 4am.