The New Zealand national has been detained on the Shonan Maru No. 2 and will be arrested after the ship arrives in Tokyo on Friday morning in what the Coast Guard said is its first case involving trespassing on a ship in international waters.

While the Tokyo police have placed three Sea Shepherd members on the international wanted list for sabotaging a Japanese whaling vessel in it will be the first time that Japanese investigative authorities arrest a member of the group.

The New Zealander, the captain of the Sea Shepherd vessel Ady Gil, is accused of approaching the Shonan Maru No. 2 by jet ski and illegally boarding the vessel on Feb. 15, according to the investigation.

The police will increase security around the port in Tokyo in preparation for possible protests.