A Golders Green historian has revealed for the very first time how British intelligence services knew about the Holocaust during the Second World War and chose not to provide evidence to Nazi war crime trials.

Dr Helen Fry, 45, made the sensational discovery while trawling through thousands of intelligence documents compiled by MI5 and MI6 throughout the war, which were declassified in 1999.

She discovered that British forces were using German refugees, known as “secret listeners”, to listen in on bugged conversations between German prisoners of war, including high-ranking army generals, held at stately homes around the UK.

Earlier this month, the mother-of-three released a book, titled The M Room: Secret Listeners who Bugged the Nazis, documenting her years of research.

She said: “This book reveals for the very first time what British intelligence knew about the extermination of Jews and how early.

“It also reveals why that intelligence was never used in the war crime trials in Nuremburg to bring the German generals to justice. There are tonnes and tonnes of material and people thought it was boring; I think that’s why historians missed it.

“But when you read the intelligence, [you find] there was little we didn’t know about Nazi Germany.”

Dr Fry presented her findings at the Dark Secrets And Silences lecture at the London Jewish Cultural Centre (LJCC), in North End Road, Golders Green, on Monday.

She was joined at the special president’s lecture by historian Trudy Gold and award-winning filmmaker Rex Bloomstein, who has directed numerous Holocaust-related documentaries.

During the evening, the three speakers discussed what the British Foreign Office knew about the Holocaust during the war and whether they could have done anything to stop it.

It was revealed that all the intelligence gathered relating to the Holocaust was never provided to the Nazi war crime trials for fear it would jeopardise other important intelligence including information relating to the development of the atomic bomb.

“They had to live with the knowledge that what they [found] 60 years ago was never used to bring these people to justice,” said Dr Fry.

The LJCC will be hosting the launch of Dr Fry’s book on January 29, where she will be joined by 93-year-old Fritz Lustig, one of only two surviving secret listeners and now a Muswell Hill resident.

For a more in-depth look at Dr Fry’s findings and the story of the secret listeners, see next week’s Ham&High.