Tourism officials in a Japanese beach town are getting increasingly concerned over unruly dolphins.
There has been a spate of attacks on swimmers at Suishohama beach in Mihama, Japan.
There were four dolphin attacks at the weekend.
A man suffered broken ribs swimming off the beach and a second man was bitten in separate incidents on Saturday.
There were two further attacks on Sunday.
There have now been six dolphin attacks on humans this year.
Officials warned swimmers to be vigilante and not approach the dolphins.
While known for being playful and generally non-threatening, dolphins can become aggressive if provoked.
Signs have been erected near the beach to warn people.
A town official advised beachgoers top stay out of the water id dolphins are spotted in shallow waters.
