WELLINGTON, New Zealand -- An anti-whaling activist group accused a Japanese whaling vessel of intentionally ramming two of its ships Wednesday in waters near Antarctica.

Sea Shepherd Conservation Society founder Paul Watson said he was aboard the ship Steve Irwin when the Japanese boat Nisshin Maru collided with it, the Bob Barker and a tanker used to refuel the Japanese fleet.

Glenn Inwood, a spokesman for Japan's Tokyo-based whaling organization, said he was seeking more information.

Watson claimed the Japanese boat deliberately rammed the Sea Shepherd boats to try to move them aside and get to the refuelling tanker. He said the Japanese boat also accidentally hit the tanker. He said the incident, near the Australian Davis Research Base on the Antarctic coast, was particularly dangerous because the tanker was involved.

He said the Bob Barker sustained the most damage. He said that boat initially put out a distress call to Australian maritime authorities after it lost power and began taking on water, but that the crew had gotten the situation under control. He said nobody from the Sea Shepherd fleet was injured.

Australian Maritime Safety Authority spokeswoman Jo Meehan said they were aware of the reports but weren't involved in any active search-and-rescue operations.

Sea Shepherd boats and the Japanese whaling fleet have had past clashes and collisions.

Australia's Environment Minister Tony Burke said in a statement that he was aware of the reports and was seeking more information.

"The government condemns so-called 'scientific' whaling in all waters and we urge everyone in the ocean to observe safety at sea," Burke said.

Japan says it hunts whales for scientific purposes, an allowed exception to an international whaling ban, though activists say the hunts are a cover for commercial whaling because whale meat not used for study is sold for consumption in Japan.

Japan decries Sea Shepherd as a terrorist group that risks lives through tactics used to obstruct the whaling fleet.

Watson, who holds dual Canadian and U.S. citizenship, said last month he was stepping down from the society in order to comply with an injunction handed down by a Seattle court in December.

The 9th U.S. Circuit Court of Appeals ordered the organization to stay at least 457 metres away from Japanese whaling vessels off Antarctica.

Watson said the anti-whaling campaign will continue under the leadership of former Australian senator Bob Brown, adding he himself will participate only as an observer under the terms of the injunction.

In July, the 62-year-old fled from Germany after being arrested at the behest of the Costa Rican government, which is pursuing him on a warrant that claims he endangered a fishing vessel crew in Guatemalan waters in 2002.

Watson, who was born in Toronto, left Greenpeace in 1977 to set up the more action-oriented Sea Shepherd.

With files from The Canadian Press