MI5 - Security Service

MI5 The Security Service

Report a threat

To report an imminent threat call 999 or ring the Anti-Terrorist Hotline on 0800 789 321

To report non-urgent suspicions:
Contact Us here


Current UK threat level


Read more about threat levels >>

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The Security Service (MI5) is responsible for protecting the United Kingdom against threats to national security. This website provides information about the Security Service, the threats it counters, links to sources of security advice and details of careers with the Service.

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A Modern MI5

28 October 2015

Andrew Parker delivered the 2015 Lord Mayor's Defence and Security lecture....

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Gathering intelligence

The collection of
intelligence is at the
heart of MI5's work.