British royal Prince Harry lashed out at a photographer on Friday night, threatening to punch the snapper in the "f**king face".

The prince had been enjoying a night out in London with his girlfriend Chelsy Davy when he became angered at the presence of the papparazzo.

An eyewitness tells British newspaper The Sun, "Harry totally flipped out. He was screaming at (the snapper) and kept shouting, 'I'll punch you in the f**king face', while the photographer looked on stunned. At one point Harry ran straight for him.

"She (Davy) looked really angry and upset, as if she had just had a fight or something. Then Harry also came out almost straight away and started running down the street after her.

"He didn't see the photographer at first but as soon as he did he started shouting at him, 'Don't you dare'. Then he ran straight at him.

"At this point a car came screaming down the street and a security guy came out and dragged Harry into the back. Chelsy was already in there."