Greenpeace scored an unsettling publicity coup on Monday morning by successfully breaking into at least one French nuclear power plant to highlight the vulnerability of atomic sites around the country, reports The Daily Telegraph.
Nine members of the environmental group managed to bypass security to enter the nuclear compound at Nogent-sur-Seine, just 60 miles south of Paris and the closest plant to the capital.
French energy giant Electricité de France, EDF, insisted the intruders were "immediately detected" after the "illegal" predawn raid and that gendarmes arrested seven of them "without the use of force". The remaining two were arrested late morning.
The French interior ministry and EDF, which owns the main UK power operator British Energy, said the incursion did not affect the security of the site.
But Greenpeace announced that some of its activists managed to "scale the dome of one of the reactors, where they unfurled a banner stating: "Safe nuclear (energy) doesn't exist".
EDF also said activists' banners were hoisted on two other of its sites - Chinon in northwestern France, and Blayais in the southwest - before they were quickly taken down.
The state-controlled group said activists were kept out of these two plants and a third, Cadarache, in the southern Bouches-du-Rhône region.
But in further embarrassment for EDF and the French government, Greenpeace insisted it had successfully penetrated "other nuclear installations" without naming them, and that several activists "are able to move around in these sites without being spotted".
"We are in the process of making a detailed search of all nuclear plants and installations to ensure no Greenpeace militants are hidden there," said an interior minister spokesman.
Eric Besson, the French industry minister, conceded that it appeared there had been security "failings".
If the intrusion were "confirmed", the nuclear industry would "have to take measures to ensure it doesn't happen again," he said.
Read more of this report from The Daily Telegraph.