Paris (CNN) -- France's interior minister admitted Monday that lapses in security made it possible for Greenpeace activists to gain entry to a nuclear power plant southeast of Paris.
Interior Minister M. Claude Gueant said there have been lapses in the nuclear plant's security system and has ordered a search of all nuclear plants, a spokesman for the ministry told CNN.
The environmental activist group said on its website that members gained entry to the plant at Nogent-sur-Seine at dawn and managed to climb the dome of one of its two reactors "in order to spread the message: 'Safe nuclear does not exist.'"
"This action shows how vulnerable the French nuclear centrals are: Peaceful activists have managed with a few means, to reach the heart of the nuclear central! Why? How? Because the security device is insufficient," the website stated.
President Nicolas Sarkozy, during a news conference with German Chancellor Angela Merkel, called the act "irresponsible," but said that the government will "absolutely publish all" of the audits related to plant security.