When your chosen fishing spot is a pond inside a park in central Folkestone, it's fair to say you're not expecting to catch anything too exotic. Hence Derek Plum's shock when, after a 15-minute struggle, he reeled in a piranha.
The 46-year-old caught the half-kilo carnivorous predator at Radnor Park pond in the Kent town, some way from its normal South American habitat.
"I felt an almighty tug on my rod – next thing I knew it had dragged my line about 500 yards. It was going all over the place," Plum told the Sun newspaper.
"Luckily, the fishing hook had fallen out of its mouth otherwise I would had somehow had to remove it myself."
The Environment Agency said the fish had probably been kept as a domestic pet, but was released when it became too big for its tank.
Ben Weir, a fishery scientist of Angler's Mail magazine, said today: "I used to keep them and they would sharpen their teeth on the glass of the tank, so I know one when I see one.
"It's probably become too big for its tank but it's extremely irresponsible to release it like this.
"They are a top-end predator. I'm extremely shocked that this has happened."
The fish was identified as a red-bellied piranha, whose diet consists mainly of fish, insects and worms. The chairman of the local angling club said a member had seen someone emptying a container into the pond the week before the piranha was caught.
Paul Foot said: "Our pond gets dumped full of goldfish and the odd koi carp because people cannot afford to keep them. It's unusual that this fish survived because the weather has been so cold."
Piranhas are among some of the most ferocious predators in the world and generally attack in large numbers. They usually feed on insects and fish but have been known to strip large animal carcasses such as cows and horses.
There are over 20 species of piranhas which grow to an average of between 20cm and 30cm, although some as long as 60cm have been found.
Experts said piranhas cannot survive long-term in UK waters, but that the introduction of non-native species into the waterways can cause serious harm.
In August 2009 a freed pet piranha was also found in the River Torridge in Devon.
The Environment Agency have urged people to seek advice rather than freeing exotic animals into the wild.
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