Two activists were held captive on Tuesday by the Japanese whalers who boarded the whaling vessel in the Southern Ocean.

According to the Sea Shepherd Conservation Society, the two activists came on board of Yushin Maru 2 in order to tell the Japanese whalers that the hunting is now illegal due to the fact that the Australian court banned the hunting along its coastline or off Australian Antarctic territory.

The society accused the whalers for taking hostage the pair, Australian Benjamin Potts and Briton Giles Lane.

In the statement which the society released it said: “Both men were assaulted and then tied to the railings of the whaler. They were then moved and tied to the radar mast by the whalers,” AFP reports.

Japan is saying that the accusations were “completely untrue.”

Minoru Morimoto, the director general of the Institute of Cetacean Research, said in a statement: "It is illegal to board another country's vessels on the high seas. As a result, at this stage, they are being held in custody while decisions are made on their future."

The statement released by the Sea Shepherd said that its captain announced the Australian police and wanted kidnap charges to be brought against the whalers.

On Tuesday Australia's Federal Court banned Japan from whaling in its coastal waters or off Australian Antarctic territory.

The Japanese fleet launched last year a plan to kill 1,000 whales in the name of science, but Australia along with other nations believe that this can be done through non-lethal methods and accuse Japan for commercial whaling.  

Australian Judge James Allsop discovered that the Kyodo Senpaku Kaisha Ltd Company killed whales in the Australian whale sanctuary thus breaking the Australian law.

Allsop said: “The court orders that the respondent be restrained from killing, injuring, taking or interfering with any Antarctic minke whale, fin whale or humpback whale in the Australian Whale Sanctuary.”

The Sanctuary expands over 200 nautical miles.

A Fisheries Agency official in Tokyo declared: "We cannot comment on a matter concerning another country's legal system. But we are not considering stopping our activities."