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. \"Lethal research\" is allowed, but other nations and environmental groups like Sea Shepherd condemn it as disguised commercial whaling. Tokyo says the whale hunts are needed to substantiate its view that there is a robust whale population in the world. However, it makes no secret of the fact that whale meat from this research ends up on dinner tables and in restaurants. The statement condemned Sea Shepherd\'s actions as \"life-threatening\". \"Sabotage activities against the research fleet by SSCS and Paul Watson have been escalating over several years,\" it said. \"The activities perpetrated by SSCS and Paul Watson not only put at risk the safety of the research vessels at sea but are also affecting the scientific achievement\" of the programme, it said. In February, Japan cut short its hunt for the 2010-2011 season by one month after bagging only one fifth of its planned catch, blaming interference from Sea Shepherd. Peter Bethune, a New Zealand national and member of Sea Shepherd, was deported from Japan in July last year after receiving a suspended two-year sentence for obstructing Japanese whalers. The legal action came after the whaling fleet left port Tuesday for this season\'s annual hunt. The coast guard has deployed an unspecified number of guards to protect it from anti-whaling activists. Japan has confirmed it planned to use some of the public funds earmarked for quake and tsunami reconstruction to boost security for the hunt.