A passerby has risked his life to tackle a man wielding a machete after a smash-and-grab robbery on a luxury City jewellers.

The have-a-go hero is yet to be identified but the whole incident was caught on a member of the public's camera phone.

The drama unfolded after the Carr Watches and Diamonds shop in Liverpool Street was targeted by three men on mopeds on Thursday at around 2:30pm.

Credit: Evening Standard

A plain clothed police officer also confronted the man before the suspect fled the scene.

Credit: Evening Standard

The man was later arrested in Gravel Lane and the machete recovered.

He has now been charged with conspiracy to rob and threaten a person with a knife/bladed article in a public place and has been remanded in custody.

Credit: Evening Standard

The two other men escaped and are still on the run.

Watch the dramatic video here: