Known in Papua New Guinea as 'The Ball Cutter', the pacu has reportedly been responsible for the deaths of two fishermen in the Pacific nation,
died from blood loss after the fish had bitten off their testicles.
Initially thought to be a piranha, the fish caught in June was later confirmed by the Illinois Department of Natural Resources to be a pacu.

Although part of the same family, the pacu has thicker, sturdier teeth that resemble human ones, unlike the piranha, which is renowned for its deadly serrated incisors.