To report an imminent threat call 999 or ring the Anti-Terrorist Hotline on 0800 789 321
Current UK threat level: SEVERE Read more about threat levels >>

THE COLD WAR

The Second World War ended with Europe divided between the two superpowers, the United States and the Soviet Union. Subversion and Soviet espionage were key concerns during the Cold War, and from the 1970s onwards terrorism also emerged as a serious threat to national security.


The story behind the 1947 controversy at a British interrogation centre in Germany

How MI5 worked to ensure the security of the late British Empire and the early Commonwealth

How one of the Soviet Union's most valuable spies in the UK was exposed by MI5. Includes copies of original documents from the MI5 case files.

MI5's work against Soviet, Eastern Bloc and Chinese espionage against the UK in the later part of the Cold War, and the rise of terrorism in Northern Ireland during the Troubles

Did the Security Service spy on Harold Wilson? The facts behind the long-running controversy

How MI5 responded to fears that communist and Trotskyist groups were infiltrating British trade unions and political parties

Fact or Fiction?
MI1-MI4 still exist in secret.

True False

Latest News

view ALL News

Why MI5 was right for me

Why MI5 was right for me - Being LGBT+ in the Security Service

Read Full Article ›

MI5 signs Race at Work Charter

We are pleased to announce MI5 is a signatory of the Business in the Community Race at Work Charter.

Read Full Article ›