A woman who helped crack Nazi code and save thousands of Allied lives has been honoured.

Mary Davis, now 84, was a Wren who served at top secret code-busting headquarters Bletchley Park, near Milton Keynes, during the Second World War.

She manned a giant early computer called the Turing Bombe, which consisted of massed banks of dials, wires and cogs which cracked German Enigma messages.

Mrs Davis, of Furze Close, High Salvington, Worthing, has now received a gold-coloured brooch from intelligence headquarters GCHQ to commemorate her service at Bletchley.

But under the Official Secrets Act, which she signed as a teenager, Mrs Davis has not until recently been able to say a word about her wartime activities.

She even destroyed all the documents relating to this period of her life, and all but one photograph.

Mrs Davis, who was born in Hove and lived in Surrenden Crescent, Brighton, before being called up, said: “Up until a few years ago you couldn't even talk about it.

“My poor mother must have wondered what on earth I was doing.

“You signed the Official Secrets Act, which was very frightening. That was enough.

“We were conscious of how important it was, but I don't think we realised until afterwards exactly how important."