Eleven people were injured when they were attacked by piranhas as they bathed in a river.
Firefighters had to take at least four people to the local hospital on Saturday (2 Mar).
The others were able to go to A&E on their own on the same day.
The victims were bitten on their feet by the sharp-toothed fish.
They were attacked as they cooled off in the Tietê River off Pôr-do-Sol Beach in Pereira Barreto, Brazil.
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A snap shows how one victim received a nasty bite to the sole.
Blood can be seen pouring from the open wound.
Local officials have since sent biology experts to the scene.
They’ve concluded that illegal fishing and discarded food caused the mass chomping.
Officials put up warning signs banning entry to the beach over the weekend.
The piranhas that have been attacking people off Pôr-do-Sol Beach have a bite force about 30 times their body weight, according to local experts.
Piranhas, with their strong jaws and finely serrated teeth, have one of the strongest bites found in bony fishes.
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