A group of attackers blocked a victim's vehicle in the car park of a Dunedin Burger King before getting out and stabbing him with a pocket knife, a witness says.

A police spokeswoman said they were called to the stabbing at Burger King on Anderson's Bay Rd and arrived at the scene about 3pm.

They arrived to find a person had been stabbed and had received a 1cm cut to the arm.

Police know who the perpetrators were but are yet to catch them after they fled the scene.

A witness said the attackers pulled up in a van and blocked the victim's car in the fast-food outlet's car park before getting out and stabbing the victim with a pocket knife.

They then fled the scene in the van.

The witness said the attackers and the victim were known to each other and recently traded vehicles.

He said one of the attackers was "a ginger".

It appeared the victim's car was jacked up in the car park.

St John treated the victim at the scene.