London N20 is not the first place you would look for a Soviet spy base - which is exactly why the Russians put it there.

LEIGH COLLINS reports on top secret documents recently released by the Ministry of Defence and covered in a new book.

Top secret documents show there was a major Soviet spy base in Whetstone during and after the Second World War.

Soon after the Soviet Union entered the war on the side of the allies in 1941, Churchill gave permission for the Soviet news agency Tass to set up a 'radio monitoring station' in Whetstone, so that the Russians could gather news to broadcast back to their citizens.

Whetstone was selected due to its proximity to London and because it had the space to pick up signals clearly.

The substantial aerial farm that sprung up in Whetstone could study radio and radar signals and air traffic, including those connected with the air defence of London.

Despite the fact that the spy base was a large building with many large aerials on top that openly said it was a Tass office, no-one now seems to know where exactly in Whetstone it was.

Professor Richard Aldrich from Nottingham University, who has written a book on Cold War espionage, said: "There would have been significant aerials and antennae but I have not yet found anybody who could tell me where this was. I expect it is just north of the Tube station.

"It would be fantastic if one of your readers could tell us where it was. It is fascinating how poor the historic knowledge of the MoD is. They don't know any more than what the documents tell them. The problem is that the British government only preserves two or three per cent of their documents."

Local historian John Heathfield had heard of the Tass site, but did not know where it was. His colleague, Percy Reboul said: "There were a lot of big Victorian houses in the area, which were knocked down and replaced by flats."

Mr Reboul added that the base may have been a semi-detached house divided into two flats. He recalled a story where a man complained to the police that his television reception was ruined by morse code tappings and other signals from the floor above.

Apparently the police told him they knew about it and he should keep quiet.

In 1949, the USSR had developed the atom bomb and in 1951 were backing the North Koreans against the Americans in the Korean War. At that time, the British government knew exactly where the Whetstone base was and was gravely concerned.

As the site had full diplomatic immunity, there was little they could do about it.

By July 1951, Britain's Chief of the Air Staff, Sir John Slessor, had acquired evidence that the Whetstone site was using its equipment for spying.

In the top secret documents, which have recently been released to the Public Record Office in Kew, Slessor wrote: "We are gratuitously presenting our potential enemy with facilities which would be of real operational value to him in the event of an attack on this country and with information which he could not obtain from any number of spies.

"It is absolutely fantastic that, at a time when we are carrying out a great rearmament programme because of the danger of war with Russia, we should continue to present the Russians on a plate with the opportunity of learning such vital defence secrets."

Upon Slessor's instructions, the British Government asked for reciprocal arrangements in Moscow. This was denied by Stalin, giving the British Government the pretext to close the Whetstone base legitimately.

Ironically, in early 1940, a British radio monitoring station was set up in nearby Arkley to find foreign spies in Britain.

The Volunteer Interceptors (amateur radio hams) who worked at Arkley View, a large Victorian House (since demolished) on the outskirts of Arkley, detected no spies in the country.

From March 1940, they directed their attentions to monitoring enemy signals abroad. Their data was used as part of the Enigma code-breakers at Bletchley Park.

It is also known that infamous British double-agent Kim Philby used to meet with KGB agents in Oakwood. It is possible this may be connected to the Whetstone base.

The Hidden Hand: Britain, America and Cold War Secret Intelligence by Richard Aldrich will be available from all good bookshops from July 5, priced at £25, published by John Murray.

If you know where the Tass base may have been, call Leigh Collins on 020 8359 5907.

September 5, 2001 11:03