The United Kingdom’s security intelligence agency, which is based in Thames House, London. Its Director General is Eliza Manningham-Buller.
The MI5 is responsible for protecting the country against threats to national security including terrorism, espionage, and the proliferation of weapons of mass destruction (such as biological warfare). This security service supports law enforcement agencies in fighting crime and provides security advice to a range of institutions and organizations so that they are better able to reduce their vulnerability to threats.
See Also: Terrorism.
Crown Copyright. MI5. [Online, 2004.] MI5 Website. http://www.mi5 .gov.uk/output/Page18.html.