A Nazi plaque engraved by prisoners of war from the Second World War has been revealed for the first time by a man who discovered it 50 years ago.

Geoffrey Parkhurst made the find while he was playing with friends next to a river in Chelmsford, claiming the group had argued over who would keep it before he eventually returned to the stream and hid it away for himself.

The words "Es lebe unser Führer" can be found on the slab – translating as "long live our leader", in reference to Adolf Hitler. It also says "made in August 1947 by German prisoners of war".

He has kept the plaque in his garage since that day but now wants to sell it to someone with a genuine interest in wartime memorabilia.

"I don't really like giving stuff to museums because half the time they don't display things they are given," said Parkhurst. "I would rather give it to someone who was interested in it. Otherwise, it will only go back in the garage."

Parkhurst said his hobby of loitering by the river and flinging mud helped bring about the discovery as the ground became lower.

"I used to sit with friends and chuck bits of mud into the stream, which made the ground lower over time. I was with a couple of mates one day and I saw the top of the plaque poking out, so I dug it out.

"We all wanted to keep it so I had to throw it in the river, then go back later and get it out again," said Parkhurst.

"I was well pleased, because I have always been interested in wartime memorabilia. I used to collect medals."

The 57-year-old admitted he had been impressed with how one Nazi had been able to write so clearly on concrete.

"What I think is quite amazing is that it wouldn't have been easy to do such good writing in a piece of concrete," said Parkhurst. "If I moved and took this with me no one would know the history. I would sell it if anyone was interested."