In the days of the Cold War, Soviet agents hid caches of weapons around cities in Europe, including the UK.
The information comes from a KGB intelligence archive which was opened to the public today.
Secret stockpiles of small arms and communications equipment were hidden by Soviet agents fearing that tensions could result in conflict, according to a leading historian.
The documents also reveal that a British woman, Melita Norwood, was one of the Soviets’ most important spies in the UK. Norwood provided them with nuclear secrets in exchange for a lifetime pension of £20 a month.
They appear to have reneged on the promise, as payments were made only up to June 1973. Norwood died in 2005 at the age of 93.
The files are the work of a senior KGB archivist who defected in 1992 and brought the information with him to the west.
His notes do not pinpoint locations in Britain, but Professor Christopher Andrew, an historian and expert on the archive, said the booby-trapped supplies were hidden around most major Nato cities.
"Given that Britain was second only to the United States in terms of importance to the Soviets at this time, it would be remarkable if this tactic wasn't deployed here”, he said.
Norwood, code name Hola, was a clerk and secretary at the British Non-Ferrous Metals Research Association in London.
The file says: “Hola passed on a lot of valuable materials for nuclear energy, which she accessed by removing them from her boss’s safe, photographing them and then placing them back.”
The information is believed to have been important to the Soviets’ atom bomb programme.
