MOSCOW - Russian commandos armed with assault rifles and handguns seized a Greenpeace ship and detained 30 activists who were protesting oil drilling in the Arctic, Greenpeace and Russian officials said Friday. Activists aboard the the Arctic Sunrise icebreaker ship told Greenpeace officials that about 15 troops rappelled down ropes from a combat helicopter in a surprise raid Thursday night in international waters, said Maria Favorskaya, a spokeswoman for the environmental group. "At gunpoint, they rounded up all the people on board and also broke the door of the radio room, where some activists tried to barricade themselves in, " Favorskaya said. A statement published on the Russian Federal Security Service website said the Greenpeace ship was maneuvering around the Prirazlomnaya oil platform, in the Russian economic zone in the Barents Sea, and ignored signals and warning fire from a coast guard ship. The troops that boarded the ship shortly before 6.30 p.m. Thursday did not fire weapons and no one was injured during the operation, the statement said. "After the captain refused to sign the inventory [of equipment on the ship] prepared by border inspectors, a decision was taken to tow the boat to the Russian port of Murmansk for further action," the statement said. Favorskaya said the activists planned to hang a banner on the platform belonging to Gazprom Neft Shelf, a subsidiary of the Russian state-owned natural gas giant Gazprom. But she said Russian coast guard detained two activists Wednesday as they tried to climb up the side of the platform and seized the ship the following evening. "Although the episode happened in the exclusive economic zone of Russia, these are not Russian waters, and Russian border troops had no right to get on board a foreign ship, let alone threaten the crew with arms and arrest them," Favorskaya said. Our activists were peacefully protesting against drilling for oil in the Arctic and thus endangering and polluting the region, and the armed attack against them and the illegal arrest of the boat and the crew is a totally outrageous thing. Those taken into custody are from Argentina, Australia, Brazil, Britain, Canada, Denmark, Finland, France, Italy, the Netherlands, Poland, Russia, Sweden, Switzerland, Turkey, New Zealand the Ukraine and United States, the group said. Greenpeace issued a statement Friday morning saying it had been over 12 hours since the organization had had any contact with the ship, which appeared to be heading west towards Russian territorial waters. "Greenpeace International has not received any formal confirmation of possible charges, and the activists have been denied access to legal or consular assistance," the statement said. Over 20 Greenpeace offices are organizing protests at Russian embassies around the world today.