A fish with human-like teeth has been found swimming in Michigan lakes, USA.
Several anglers have hauled the odd-looking specimens out of the water, prompting a warning from wildlife experts.
They are Pacu fish.
Pet owners release the fast-growing omnivore into the wild because they become too large for aquariums.
But Nick Popoff, manager of the Aquatic Species and Regulatory Affairs Unit of Michigan’s Department of Natural Resources (DNR) said releasing the animals “is almost never humane”.
Popoff said, “Pets released from confined, artificial environments are poorly equipped to fend off predators and may be unable to successfully forage for food or find shelter.”
“Those that do succeed in the wild can spread exotic diseases to native animals. In the worst-case scenario, released animals can thrive and reproduce, upsetting natural ecosystems to the degree that these former pets become invasive species,” added Popoff.
The Pacu fish can grow up to 3ft and weigh 55lbs in the wild and have such powerful teeth to help them crunch through nuts, fruit and plants.