Two fishermen bled to death in separate incidents in June of 2001 along the Sepik river in north-western Papua New Guinea after having their penises bitten off by pacu fish. The fish are related to piranha and follow urine strams in the water, swimming to its source and then biting it off with razor sharp teeth. Some believe the killer may be a fish introduced from Brazil in 1994 as a protein substitute, but marine biologist Ian Middleton blamed another pacu species, introduced from Indonesia. "The killer fish have the most human-like teeth on the bottom jaw I have ever seen and quite possibly feed on insects," he said. The Brazilian pacu grow to 44 lb (20 kg) and have no teeth (Melbourne Herald Sun -July 6th, 2001).
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