A man fishing in a Stroud river was stunned after he 'caught' a submachine gun - dating back to 1940.
The fisherman hauled out the German World War Two weapon - along with a number of bullets from a different gun.
The rusty MP-40 was the weapon of choice for the Nazi German Army - known as the Wehrmacht.
But this one was pulled out of the River Frome by an angler - who called the police.
Experts say it is possible that the weapon was ditched by a German spy, who were known to have brought weapons to Britain.
But those were usually pistols such as a German Luger Pistol found in Hull in 2010.
It may have been brought to Britain as contraband by a British soldier after the war - or dumped by a collector.
The gun was recovered by Gloucestershire Police's Special Ops Unit who attended the scene after being called by the fisherman.
A spokesperson for the police later said: "We were called to help out a fisherman today who pulled something a bit different from the river: This German sub-machine gun is a piece of history, which could be as old as 1940, "We wouldn't advise eating this one. The weapon is going to be examined by our force armourer".
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