A US self-defence instructor who teaches pupils to "inflict crippling pain from injury to easily damaged body parts" has been barred from Britain where he was to give seminars in areas hit by 2011 riots.

Tim Larkin, who runs Target Focus Training and has been accused of promoting vigilantism, was turned back at the airport in Las Vegas on Tuesday with notice that he had been denied entry by Home Secretary Theresa May.

He had been due to speak at the Martial Arts Show in Birminghamand give classes in areas including Tottenham in north London, where a wave of rioting and looting began in August 2011, leading to unrest in which five people died.

Larkin's website says the core of Target Focus' philosophy is that "violence is rarely the answer, but when it is, it's the only answer".

It claims he has been teaching "elite military and law enforcement agencies in 58 countries" for 20 years.

The Home Office, said in a statement: "We can confirm that the individual in question is subject to an exclusion order.

"The Home Secretary will seek to exclude an individual if she considers that his or her presence in the UK is not conducive to the public good."

Larkin told BBC radio: "I think it's a gross overreaction, especially with some of the people that are allowed to come in and out of the UK."

He blamed his exclusion on negative press coverage and his call for changes to British law on self-defence, saying people were reluctant to fight back against criminals because "they're afraid of being prosecuted".

"You have an awful lot of self-defence being taught there that gives no instruction on trauma to the human body," he added.

British police have arrested over 4,000 people and charged more than 2,500 over the explosion of unrest in English cities last summer.

The riots flared in London following the death of a man in a police shooting on August 4, and quickly spread to Birmingham, Manchester and other towns and cities.