DELRAN, N.J. (WPVI) -- A fish that's native to the Amazon was caught in a pond in South Jersey over the weekend.Ron Rossi from Delran, Burlington County made the rare catch Sunday at Swedes Lake during a fishing excursion with his family."We scoop this thing up and brought it up. We didn't know what kind of fish it was," said Ron.Frank Rossi, Ron's son and fishing buddy, says he couldn't identify it either."I've never seen anything like that before in the lake. It was different," said Frank.At first, judging from its appearance, they thought it was a piranha.But after researching it on the internet, indications were that it was actually a South American a fish called a Pacu.Pacu are related to piranha but unlike their meat-loving cousins, Pacu are listed as omnivores.Also, while Pacu do have teeth they are not sharp. The Rossi's say that's how they confirmed the fish's identity."We did pull the bottom lip down to see what they looked like and they have almost human teeth. It's exactly what it looked like on the Internet," said Ron.The question now is - How did a freshwater fish from South America end up in a man-made lake in New Jersey?State officials say the answer begins with people buying Pacu from pet stores for their aquariums.A spokesperson from the DEP sent Action News a statement reading in part, "Many times, these fish are deposited into lakes by pet owners. These fish do not survive in colder water, so we encourage people not to release it into the wild but to humanely destroy the fish."The Rossi's plan on doing just that.But their lingering concern is that more Pacu remain in Swedes Lake.Their concern stems from the fact that, while rare, there have been reports of Pacu attacking people."A lot of residents swim and then there's the marathon people that swim the length of this lake just about every day," said Ron.Pacu are also a concern because they can compete with native fish for food and they could introduce exotic parasites and disease.