Japan Sends Icebreaker To Southern Ocean Whalers Australia should send vesse: Sea Shepherd The whaling conflict escalates with the arrival of Japan's giant military icebreaker Shirase, making a total of 10 vessels in the southern ocean. Japan has sent a giant military icebreaker to bolster its whaling fleet in the conflict with Sea Shepherd off the Australian Antarctic Territory, anti-whaling activists say. The 12,500 tonne Shirase, operated by the Japan Maritime Self-Defence Force, has appeared near whalers and Sea Shepherd activists 50 nautical miles off the coast of the territory, the group said. The ship was recognised on radar by its identification signal, according to Sea Shepherd. The Korean tanker Sun Laurel was making a renewed attempt to refuel the whalers' factory ship Nisshin Maru under the shelter of a Coast Guard helicopter from Shirase, Sea Shepherd founder Paul Watson said. The powerful icebreaker can carry up to 250 crew and three helicopters, and has conducted Antarctic resupply duties for Japan, according to the Japanese Ministry of Defence website. Shirase was scheduled to be in the region conducting Antarctic scientific work off nearby Cape Darnley, an informed Australian source said. The ship was due to be working on ocean moorings, which are used to collect oceanographic data. The Japanese Government had no immediate comment on the Shirase's use, or the presence of the helicopter over the Sun Laurel. Sea Shepherd Australia director Bob Brown said on Monday that he had informed Environment Minister, Tony Burke of the Shirase's presence. "We are calling again for the Australian Government to become involved and send a ship south," Dr Brown said. Comment is being sought from the federal government. Mr Watson said the Shirase's last know port was Fremantle and last position received was 86 days ago. "So I guess it has been out at sea for a while," he said. It may not be here for us specifically but is likely getting involved now. A blockade by Sea Shepherd stopped the Nisshin Maru from reaching the tanker last week. Instead the whalers' mother ship was involved in a series of dramatic collisions with the Sun Laurel, and three Sea Shepherd vessels. According to Mr Watson, after spending several days north of the ice, the Sun Laurel turned south, and early on Monday was approaching Nisshin Maru. The ships were about off Mackenzie bay, far south-west of Perth, in a wildlife-rich area of Antarctica near the Amery Ice Shelf. Mr Watson said the Sea Shepherd vessel Sam Simon had followed the Sun Laurel as it steamed through waters strewn with icebergs, and submerged ice chunks known as growlers in early morning darkness. The Sun Laurel was not an ice-class vessel, and nor was it equipped with a spotlight, he said. "This is a serious situation and the tanker should be recalled," Mr Watson said. This situation represents a real potential threat for a major oil spill in the area of MacKenzie Bay not far off shore of the continent of Antarctica. VIDEO: Sea Shepherd say this vision shows the Nisshin Maru launching 'exploding concussion grenades' and ramming their ships last week. The Japanese government has repeatedly called for Sea Shepherd to end its obstruction of the whaling fleet. Japan's consul-general in Melbourne, Hidenobu Sobashima, said the activists endangered the lives of the crew, and property, and safe navigation at sea. Mr Sobashima rejected a Sea Shepherd claim that the Nisshin Maru wanted to load heavy fuel oil, which is banned in the region. "There is no violation of (International Maritime Organisation) rules," Mr Sobashima said. Refuelling at sea inside the Antarctic Treaty area is not illegal, according to Australian experts.