Piranhas have never before been seen at the Daveron beach in Caceres, western Brazil, which is popular with tourists.

But despite the Piranha invasion, beach authorities in the beach town are insisting the beach stay open for the sake of tourism.

“People have got to be very careful. If they’re bitten, they’ve got to get out of the water rapidly and not allow the blood to spread,” firefighter Raul Castro de Oliveira told Globo TV’s G1 website.

Daveron officials have put up large signs warning swimmers about the piranhas. In blood lettering, they read: “Attention swimmers. Area at risk of piranha attacks. Danger!”

A swimmer at the beach, Elson de Campos Pinto, 22, who got bitten, said: “I took a dip in the river and when I stood up, I felt pain in my foot.

“I saw that I had lost the tip of my toe. I took off running out of the river, afraid that I would be further attacked because of the blood. I’m not going back in for a long time.”

Another swimmer, Roselene Fereira, 45, was nipped on her toe by a piranha Sunday.

“It was all over in minutes. I felt a sharp pain in my foot and when I looked, I had a huge wound on my toe and it bled a lot.

Everyone ran out of the water and I panicked,” she said. “I was with my granddaughter playing in the shallows … I just know I’ll never get in the river [again].”

Piranhas have also been caught by local fisherman Hildegard Galeno Alves. He said he pulls them in with his fishing net.

“I come here with my kids and I always see blood on the river banks.

“The worst is that the attacks are in shallow water, next to the bank.”

Despite making his living off the river, Mr Alves left no doubt about his feelings for the water.

“I would never even think of going in there,” he said.

Gonzaga Junior, a spokesman for the city government, said: “Everyone knows there are piranhas in the region and have always taken the necessary precautions,” he said. “What is different this time is that they’ve appeared where they never appeared before.”

The city has seen far fewer people than normal use the beach recently because of the piranha attacks. It was deserted Tuesday, a national holiday in Brazil, normally a heavy beach day.

Piranhas, commonly found in  South America, are well known for their razor sharp teeth, and have a reputation for having voracious appetites. They are known to occasionally attack large animals, but they also eat fruit, seeds, and fish. Some have been found with bird fragments, snakes, and small mammals in their stomachs