The Security Service's headquarters are at Thames House in central London. Built in the Imperial Neoclassical style in 1929-30, Thames House was used as a commercial office block before the Security Service moved there in 1994
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