Threat levels
Featured page
Documents from three famous 20th century spy cases involving British, German and Soviet spies have been declassified and published on the MI5 website.
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.
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
IF YOU SUSPECT IT, REPORT IT






