The first official history of MI5 has been published to mark the British intelligence agency's 100th anniversary. Among the photographs released is this 1970 observation post used to track Soviet Bloc intelligence officers.
Professor Christopher Andrew's book, The Defence Of The Realm, contains this surveillance shot of Siobhan O'Hanlon, an IRA explosives expert and committed feminist, taken in Gibraltar in 1988.
An MI5 "Operation Airlines" surveillance photo of Donald Gannon, left, and Gerard Hanratty preparing for a foiled IRA attack on the electricity supply of Greater London. The image was taken in July 1996.
MI5's current director general Jonathan Evans, taken in May 2009 at the agency's intelligence operation centre at Security Service headquarters. The agency limited what Prof Andrew could publish.
A night time training exercise for covert entry into a target building. Prof Andrew was given access to all 400,000 files created by MI5 since it was founded in 1909.
Al-Qaeda plotter Dhiren Barot aimed to explode a radioactive dirty bomb, but admitted he lacked the contacts to construct one. He was later sentenced to a minimum life sentence of 40 years in prison.
Industrial organiser Bert Ramelson, right, and NUM general secretary Lawrence Daly at the Prince of Wales pub in Warren Street, London in 1969. MI5 believed Daly was prepared to work closely with the Communist Party.
Briton Omar Khyam meets Canadian Islamic extremist Mohammed Momin Khawaja, right, from whom he hoped to obtain electronic bomb triggers. The photograph was taken at Heathrow in February 2004.
In July 2000, Operation Large uncovered the first bomb factory linked to Islamic radicals to be detected in Britain. Moinul Abedin, codenamed Pivoting Dancer, was later sentenced to 20 years in jail for bomb making.
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