SHY 16-year-old Thomas Brown was well-liked among his shipmates - the humble kitchen assistant was the one who doled out the cigarettes and the odd bar of chocolate.

But nobody aboard HMS Petard in 1942 dreamt that the ship's 'baby' would be instrumental in one of the most daring missions of the Second World War which was thought to have shortened the conflict by 12 months and saved countless thousands of lives.

Thomas was among the team of brave British servicemen who boarded an enemy U-boat to capture secret German documents which enabled boffins to crack the Enigma code. Now, nearly 60 years later, he is to be immortalised in his home town on Tyneside in a stained glass window.

A war hero who received the George Medal, he could never tell the story of what he had done because at the time of his death it remained top secret. Unassuming Thomas, known as Tommy to his friends, died in an unsuccessful attempt to save the life of his three-year-old sister, Maureen, in a house fire while on leave back in North Shields in 1945.

Well-known glass artist from Consett, Maralyn O'Keefe, is currently designing the window for a redesigned town hall due to be opened in North Shields in October.

His old shipmate James Crang said: "All of us knew Tommy particularly well.

"He was certainly not the dashing hero type. He seized the chance of joining the action when the German U-boat, the U559, was brought to the surface after an attack.

"There was a sudden whoosh of water and there was the conning tower. There was a lot of excitement but we were silenced by the Captain who realised the urgency of getting the boarding away. Amid all the panic Tommy stripped off his clothes. Eluding the grasp of his canteen manager he went over the side. Ahead of the others in the official boarding party he climbed on to the tower and into the control. Afterwards her reverted to his normal self, the quiet, retiring boy of 16."

Mr Crang, of Dorset, explained that it was Thomas who actually carried the code books aboard the ship.