Since its founding 10 years ago, the British chapter of the Guardian Angels - the self-appointed vigilantes formed in New York in 1979 - has been patrolling the Underground as well as housing estates in London, Nottingham and Bristol.
Richard Hoseason, the Guardian Angels' European co-coordinator, says his squad of recruits would enhance the role of the police. "King's Cross borders two police districts, Islington and Camden," he says. "We get on well with the Holborn police, who come under Camden. We exchange intelligence and the relationship is very positive."
Ann Widdecombe, the shadow Home Secretary, supports the Angels. She says the group and similar organisations have an important role to play in crime prevention: "Efforts such as these by the Guardian Angels, if supported by the police, can work very well."