An author from Greystoke, near Penrith, has released a book on one of the most outrageous and least known missions of the Second World War.

Mel Kavanagh, has written the book ‘Hitler’s Spies: Lena and the prelude to Operation Sealion.'

The book details the little known Operation Lena - which is dedicated to the story of the first four German spies who successfully arrived in the South of England and uses a wealth of primary material including sources previously designated secret.

This is the first book, written in English, on the spies.

Operation Lena was part of the initial undertaking to necessitate Hitler’s invasion of England, itself codenamed Operation Sealion.

Mel, who moved to Cumbria in 2011, said the book highlights the myth of Germans being ultra efficient and also the panic involved in being a part of Hitler’s war.

These men were to be the pathfinders, the scouts, the eyes and ears that would help the first invasion of England for several hundred years.

This extraordinary story stands as evidence of the only part of the invasion actually to arrive. It shows the abysmal quality of their selection and training, and of the extraordinary fairmindedness of a British jury, especially when Britain was gripped by spy paranoia.

This is possibly one of the most audacious and least known episodes of the Second World War.

Mel comes from a family steeped with military history. His father served with the army during WWII and his grandfather was at the Battle of Jutland during WW1 aged just 16.

Hitler's Spies, by Pen & Sword Books Ltd, is available on Amazon and at Waterstones at £25.

Born in Hampshire, Mel Kavanagh spent his childhood in Surrey before joining the RAF in 1972.