(ROUGH CUT ONLY - NO REPORTER NARRATION)<br/> The anti-whaling group Sea Shepherd released on Thursday video footage of a clash between their activists and Japanese whalers in the Southern Ocean.<br/> The incident took place on Wednesday in the seas about 300 miles north of Mawson Peninsula off the coast of Antarctica, the anti-whaling group Sea Shepherd said in a statement on its web site.<br/> Sea Shepherd said the video showed their activists being attacked by Japanese whalers with bamboo poles.<br/> Reuters has not independently verified the content of this video.<br/> Sea Shepherd said three activists were injured in the operation.