Tokyo ? Tokyo’s Metropolitan Police Department is set to place three members of Sea Shepherd Conservation Society, a U.S. anti-whaling group, on an international wanted list for allegedly obstructing a Japanese research whaling ship’s activities last year, MPD officials said Monday.

On Monday afternoon, the MPD’s Public Safety Bureau obtained arrest warrants for the three – two Americans aged 30 and 41, and a 28-year-old Briton – on suspicion of repeatedly and forcibly interfering with the mission conducted in the Antarctic Ocean by the ship from a Japanese research whaling fleet in February 2007.

On Feb. 12, 2007, the three activists aboard a Sea Shepherd ship approached the Kaiko Maru, a scientific research whaling ship, and one of them threw a smoke pot onto the Japanese ship’s deck, according to investigative sources.

Two of the trio transferred themselves to a dinghy and threw a rope into the sea, which coiled around the Kaiko Maru’s propeller.