The security service MI5 and the electronic interception centre GCHQ have been asked by the government to join the hunt for people who organised last week’s riots, the Guardian has learned.The agencies, the bulk of whose work normally involves catching terrorists inspired by al-Qaida, are helping the effort to catch people who used social messaging, especially BlackBerry Messenger (BBM), to mobilise looters.
http://www.guardian.co.uk/uk/2011/aug/15/mi5-social-messaging-riot-organisers-police