Berlin aquarium staff were startled to find that a carnivorous piranha fish was recently released in the facility’s petting pool for children. The piranha, whose teeth can grow up to two centimetres (three quarters of an inch) long, had already begun taking bites out of other fish when it was found and transferred to another aquarium. The fish was so rapid that staff had to empty the pool, where children can stroke the fish swimming there, to catch it. They were puzzled about how the fish came to be there, but said tortoises and other exotic marine life had been found in the past left by people wanting to get rid of them but who didn’t dare flush them down the toilet. The razor-toothed piranha can grow to up to 60 centimetres (two feet) long and normally lives in the rivers and lakes of South America. It can be freely bought in specialist pet shops in Germany.