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1 March 2005 releases: Soviet intelligence agents and suspected agents
During the 1950s, there were a number of major spy cases, most famously that of the Cambridge spies, but also including the case of the atomic weapons scientist Klaus Fuchs, who provided the Russians with the secrets of the atomic bomb.
Many of the Soviet spies uncovered in the 1950s had begun working for the Russians years earlier and had lengthy histories of involvement with the Communist movement. But in the absence of a comprehensive vetting system for those employed in sensitive government posts - which was not introduced until 1948 - many of these links were missed. Jurgen Kuczyinski, who was a key player in the Fuchs affair, was a case in point.
Jurgen Kuczyinski
File ref KV 2/1871-1880
Jurgen Kuczyinski
Jurgen Kuczyinski, a German statistician whose father was working at the London School of Economics and who joined him in Britain in 1936, was well known as a Communist even before his arrival in the UK.
He first came to Security Service notice in 1931 through intercepted correspondence. His mail was watched throughout the war, and his father, sisters and brothers-in-law were all subject to the Service's attentions.
Yet despite this continued monitoring, Kuczyinski's role as the man who introduced atom spy Klaus Fuchs to Soviet Intelligence was completely missed, and he secured employment during the war with the US Bombing Research Mission. The Service did not oppose this appointment, recognising that his technical skills would be useful, but the Americans were warned not to give Kuczyinski a chance to further his political beliefs.
His connections to Soviet Intelligence were first suspected when his sister, Ursula Buerton, was named by British spy Alan Foote as a Soviet Intelligence agent in 1947. They were finally confirmed in 1950 when Fuchs named Kuczyinski as his first contact.
This file is the last to be released on the key personalities from the Fuchs spy case.
