CONSTABLES called to a nocturnal disturbance in Windermere found a group of men cheering two battling plesiosaurs, it has emerged.
The gang fled, but one of the monsters was so badly hurt that it had to be put down.
Plesiosaurs, although harmless to humans and labradors, are territorial and will fight other dinosaurs if they are introduced to their lake.
In recent years criminal gangs have begun exploiting this instinct by removing creatures from their native regions and transporting them to another body of water where a plesiosaur is known to reside.
PC Roy Hobbs said: “Lake monster fighting is a growing trend among the criminal underclass who either wager large sums of money on the outcome or simply enjoy the bloodthirsty spectacle of huge saurian beasts ripping chunks out of each other.
“Either way, they go to a considerable amount of trouble as the logistics of capturing and transporting a dinosaur are far from straightforward.
“Usually they will go to a lake or loch and lob in a dead sheep containing an anchor which sticks in the monster’s throat. Then they reel it in, like a massive carp, and stick it in a big tank of water on the back of a lorry.
“Often they simply die in transit because it’s not proper lake water.
“Makes you sick really.”
He added: “We took a number of close up photos of the dead dinosaur to use as evidence but they came out blurry and indistinct, like always.
“Obviously you expect that but it’s still frustrating.”