Sea Shepherd activists set sail for Antarctic to battle Japanese whalers

Fast new patrol vessel built with Dutch, British and Swedish lottery funds aims to challenge Japan's defiance of international court ruling on whaling

Two ships have left Australia bound for the freezing Southern Ocean to confront the Japanese whaling fleet in an annual high-seas battle, the environmental activist group Sea Shepherd has said.

The organisation's flagship, Steve Irwin, departed for Antarctic waters on Monday along with a fast new patrol vessel, Ocean Warrior, built with financial support from the Dutch, British and Swedish lotteries.