The vicious giant snakehead eats everything it comes across and has even been reported to kill people.
The monster — from south-east Asia — has a mouth crammed with fearsome teeth, can “crawl” on land and survive out of water for up to four days.
An Environment Agency source said last night: “The reaction was, ‘Oh s***’. This is the ultimate invasive species — if it starts breeding here it’s a disaster.”
Angler Andy Alder caught the snakehead while using a sprat as bait for pike on the River Witham near North Hykeham, Lincs.
Andy, of Lincoln, said: “It had a gob full of razor-sharp teeth. To be honest it looked terrifying.”
Experts who studied photos of Andy’s catch confirmed it was the predator which is on a list of species that cannot be imported into the UK.