An activist fighting to save whales has claimed that Japanese whaling ships have attacked vessels belonging to an anti-whaling group called, Sea Shepherd.

Bob Brown, a member of the board of directors of Sea Shepherd Australia said that Japanese whaling ships rammed into and hurled concussion grenades towards Sea Shepherd ships. He said that the attack by the Japanese ships is the worst incident for the group since one its ships sank two years ago.

"There's been the most outrageous attack on the Sea Shepherd Australia ships today," said Brown. He also said that large Japanese factory ship, the Nisshin Maru rammed into Sea Shepherd ships in the Southern Ocean near Antarctica where it was refuelling. He also claimed that a Japanese government escort vessel shot water cannon and concussion grenades towards the activists.

He also claimed that the Japanese ships had intruded into Australian territorial waters and accused the ships of violating both international and Australian law. The Japanese Ministry of Agriculture, Forestry and Fisheries has responded by saying that it is checking to obtain more information about the incident but was not able to comment further.