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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MI5 named employer of the year by Stonewall

19 January 2016

MI5 has achieved 1st place in the annual Stonewall Workplace Equality Index...