Dolphins wounded four people in attacks off the Japanese coast this weekend, according to local media. Experts say dolphins can become aggressive, but attacks are rare. Local authorities say they have so far recorded six dolphin attacks on humans this year, Asahi Shinbun reported. And last year authorities installed ultrasonic transmitters in Koshino Beach, Fukui Prefecture, after a series of dolphin attacks, according to reports. It's unclear from the reports what kind of dolphin is believed to be responsible for these recent attacks.

---

Persons: Asahi Shinbun Organizations: Dolphins, Service, Asahi Shinbun, Tsuruga, BBC, Asahi Locations: Mihama, Fukui prefecture, Wall, Silicon, Japan, Fukui Prefecture, Koshino Beach