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September 2019 release of historical MI5 files

Underwater Detection Establishment in PortlandMI5 has released a new batch of historical files to The National Archives, where they are now available to view. The majority relate to the Portland spy ring - five Soviet spies, three of whom were ‘illegals’ living in London under deep cover, who were arrested in 1961 for stealing naval secrets from the Underwater Detection Establishment (UDE) in Portland. Their disruption marked one of the Service’s most significant post-war counter espionage successes.

This batch of files focuses on the three Russian illegals. Gordon Lonsdale – whose real name was Konon Molody - was the KGB officer who ran the spy ring in the UK, posing as a Canadian businessman. As well as letters he exchanged with his wife in Russia, his file includes a series of interviews between him and MI5 officer Charles Elwell following his arrest in 1961, in which he talks with surprising candour about his life as an illegal spy. Peter and Helen Kroger, really Morris and Lona Cohen, posed as antiquarian booksellers while running a communications hub from their Ruislip bungalow, transmitting the stolen secrets back to Moscow. 

Lonsdale’s two identified agents were British nationals Harry Houghton and Ethel Gee, who worked at the UDE and had access to secret intelligence, which they regularly passed to Lonsdale over a number of years – a large proportion of their files were released to The National Archives in November 2017, and the remainder in this release. You can read more about the Portland Spy Ring in our History section.

This release also includes files related to numerous foreign agents and intelligence officers, including Arnold Deutsch - instrumental in recruiting the Cambridge Five – as well as communists and right-wing activists. Read more about these releases on The National Archives website.

24 September 2019


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