Authorities in the Spanish city of Benidorm have warned residents and tourists to avoid swimming at the beaches after 15 bathers were attacked "piranha-style" predatory fish.
The famous Poniente beach has seen many such bites in recent days.
The fish special behind the bites, Oblada melanura, usually feeds on invertebrates such as crabs, but it feeds more often as its metabolism rises in higher temperatures, as has happened in Benidorm. They can grow to 30 cm in length and are identified by a black spot on their tails.
Spanish media reported that the majority of the victims were bitten on parts of their bodies where they have wounds or moles. Obladas bites are capable of drawing blood when biting a human.