London pedestrian pounces on machete-wielding jewellery thief

This is the moment a smartly-dressed London man decided to tackle a jewellery store robber armed with a machete.

Some have branded the passerby as a hero, while others have labelled him a fool after his daring leap onto the robber's back on Thursday.

The video footage shot by a pedestrian shows a trio of robbers armed with large knives and sledgehammers fleeing a upmarket jewellery shop in London's financial district.

As two of the robbers climb aboard mopeds and drive away, the third runs away on foot.

It is at that moment a pedestrian sporting a blue suit and tie pounces upon the back of the man in black.

"I saw him jump on him, then it was a bit of a piggy back ride," a worker in a nearby shop told the Telegraph.

"Then the guy pulled out a machete and he backed off."

Police followed the suspects to a car park, where one of them was arrested.

The two others are still at large.