TOKYO - Japan's whaling authorities said Friday they were suing campaign group the Sea Shepherd Conservation Society and its head in the United States in a bid to stop it from interfering in the annual whale hunt.
It is the first time that Japan has attempted legal action abroad against anti-whaling campaigners, who have sometimes used extreme methods against ships involved in the hunt, carried out under rules that allow research whaling.
"Today, Kyodo Senpaku Kaisha and the Institute of Cetacean Research along with research vessels' masters filed a lawsuit against the Sea Shepherd Conservation Society (SSCS) and Paul Watson," they said in a statement.
"The Institute of Cetacean Research and Kyodo Senpaku are seeking a court order in the US District Court in Seattle, Washington that prevents SSCS and its founder Paul Watson from engaging in activities at sea that could cause injuries to the crews and damage to the vessels."
Kyodo Senpaku owns ships, while the cetacean institute operates the "research" whaling programme under the authority of the Japanese government.
Sea Shepherd, based in Washington state, regularly sends vessels to harass the whalers.
In previous years it has thrown stink bombs onto the decks of the Japanese fleet, while vessels from both sides have repeatedly clashed.
The Japanese statement said the whaling programme was "greatly contributing to the advancement of scientific knowledge of whale resources in the Antarctic".
Commercial whaling was banned under a 1986 International Whaling Commission agreement.