A six foot boxer who witnessed a man assaulted on Wimbledon Common this morning has told of his horror of discovering the man "beaten to the pulp".

Russell Reed was walking the dog with his wife when they heard cries for help and rushed to bushes near the Windmill cafe at about 6.30am this morning.

He said: "When we got there this man was on top of him. He was saying this man has nuclear warfare, he's going to kill and he was trying to kill him.

"He was on top of him in the bushes, it looked like he had been punching him for a while. This man's eyes were black.

"There was a bone sticking out of the side of his wrist."

Mr Reed said the attacker appeared to be an Eastern European man who was walking off when police arrived and arrested him.

He said: "The guy being beaten up was a well-to-do man. The Englishman said please help me I'm a good man."

London Ambulance Service was called just after 6.40am and took the injured man, reported to be in his 50s, to hospital.

They said his injuries are not thought to be life-threatening.

Mr Reed said: "I'm a boxer so I have seen plenty of black eyes and bruises and in my eyes I believe it was more of an attempted murder."

Police arrested a man in his 30s and he is currently in custody at a south London police station.