The newly-declassified documents include details about some of the UK's most notorious spies.

Top secret MI5 files detailing first-hand accounts of confessions of three of Britain's most notorious double agents including Kim Philby and Anthony Blunt who spied for the Soviet Union were released for the first time on Tuesday.

As new documents reveal fascinating new details about the infamous MI6 double agent Kim Philby and his betrayals, Mark Hollingsworth reflects on how despite the evidence, he and fellow Soviet agent An

A World War II-era tailing guide is among declassified records shedding light on spy game in MI5: Official Secrets, at the National Archives.