A young boy from Oklahoma caught a strange piranha-like fish with scary human teeth hidden behind the fish’s lips.

According to a Facebook post from the Oklahoma Department of Wildlife Conservation (ODWC), Charlie Clinton caught an exotic fish known as a pacu in a “neighborhood pond” over the weekend of July 15.

“Paku is the name of several species of fish in the family Serrasalmidae. They are native to South America and are closely related to piranhas, with a body shape similar to their razor-toothed cousins. Pacus enter U.S. freshwater ecosystems when people keep them as pets, but are irresponsibly released into nearby ponds and rivers when they become too large for aquariums,” wrote the ODWC.

“The exact type of Clinton spear captured is unknown, but this group is known to have reached a length of about 3.5 feet (1 meter) and weighed 88 pounds (40 kilograms),” ODWC officials wrote.

Despite their resemblance to piranhas, paku are harmless to humans. According to the American Museum of Natural History (AMHN), its flattened, human-like teeth are the result of a diverse omnivorous diet that includes small fish, hard-shelled crustaceans, fruits from freshwater plants, and nuts.

According to AMNH, paku also help fertilize and seed freshwater plants, making them an essential species in their native ecosystems. However, like many other invasive species, these fish can have negative effects on the ecosystems they enter.

“The practice of dumping unwanted pets into waterways can be incredibly harmful to local wildlife,” ODWC officials wrote in a Facebook post. “This is an exotic, invasive species that can wreak havoc on our local ecosystems.” In this context, they added that fishermen are asked to remove them from rivers and ponds wherever possible.

In 2018, Kennedy Smith, who was 11 at the time, caught a disc weighing about 0.5kg in an Oklahoma lake. While the humanoid rodents did little damage, they bit off their grandmother’s finger when they tried to unhook, USA Today reported at the time.

“I was confused because I knew fish with teeth weren’t normal,” Smith told USA Today. “It was amazing. They looked like humans and that made them even weirder.”