He said police in London and elsewhere faced the challenge of tackling relatively small gangs who have moved quickly between shopping centres.

Richard Garside, the director of CCJS, is critical of Mrs May's post-riot strategy for tackling gangs.

"Trident is a key part of how we tackle gangs and remains responsible for preventing and investigating shootings in London."

Three of the UK's most important criminal justice watchdogs warned in 2010 that efforts to tackle teenage gangs were missing important opportunities to rescue youngsters from criminality.

Furthermore, evidence at home already shows that measures already used to tackle gangs have similarly targeted and discriminated against minority ethnic children.

IDS's ratings have risen since the riots - perhaps because of his new responsibility to tackle criminal gangs.

Operation Trident is not the way to tackle gangs.

Despite Colombian President Juan Manuel Santos' promise to tackle drug trafficking and gangs, Colombia is still the world's number one producer of cocaine.