"It started virtually as I stepped in the door," Mr Welsh said.
He could see shopkeeper Rajbir Singh trying to take a bag off the young woman who was with two males - she had stuffed a box of bourbon and cola cans into it and tried to leave.
"They were going to do a runner. I said 'You're not taking that' and she said 'Yes I am' - then it was all on."
Mr Welsh said it all happened quickly and at one stage all four of them were on the floor scuffling.
"It was just a flurry of blows."
He took several hits to the head and also received a gash to his right arm.
At one stage he got up and grabbed at bottles one of the group had gathered up, and scooped them behind the counter.
"I didn't want them to get away with anything," he said.
"Why can't they earn some money and buy it like everyone else."
He reckoned they may have got away with a couple of bottles, although dropped and broke one on the way to their car which was about 30m up the road with at least one other person in it.
While Mr Singh got the first three letters of the registration, he got the numbers and passed them on to the woman who had spotted it all unfolding in the first place.
"She was on to the police at that stage. They were here pretty quick but they [offenders] could have shot off through Whakatu or Haumoana."
He said the group did act strangely in that they appeared in no desperate hurry to take off after they got to their car.
He feared they may have decided to "grab something" and go back for another go.
Mr Wilson said Clive was a tranquil spot and in his years of working there he had never come across anything violent like it.
"We had a couple of shoplifting hit and runs, but nothing major."
Detective Sergeant Mark Moorhouse of the Hawke's Bay CIB said the car used was a white 1992 Nissan Maxima which police are seeking sightings of, or information about.
"We want to hear from anyone who saw the car or saw these people."
Two male Maori and a female, believed to be in their teens, were involved.
There was also at least one other person waiting in the parked car.
The female was wearing a black top and trousers while one of the males was wearing a cap and black hooded top, reddish trousers and black and white sneakers.
No arrests had been made at this stage although inquiries into the registered ownership of the car were being carried out.
Anyone with any information about the incident or the offenders is asked to call Hawke's Bay Police on 831 0700 or call Crimestoppers on 0800 555 111.