French agents have arrested a researcher from Europe's top atomic lab on suspicion of links to al-Qaeda, fuelling fears that terrorists could be targeting the nuclear industry.
The 32-year-old man, who was detained along with his brother, works for the prestigious European Organisation for Nuclear Research (Cern) in Geneva, Switzerland, according to French police sources.
''The inquiry will doubtless say what were the objectives in France or elsewhere and indicate perhaps that we have avoided the worst possible scenario,'' said Brice Hortefeux, the French Interior Minister.
An intelligence source told Le Figaro that ''this is a very high level'' case.
The suspect is believed to have been in contact with members of al-Qaeda in the Islamic Maghreb (AQIM), an Algerian-based terrorist organisation which joined Osama bin Laden's network in 2007.
A source said French intelligence officers had intercepted messages in which the man had suggested targets in France.
''He had expressed a wish or a desire to commit terrorist actions, but had not materially prepared them,'' said the source.
The suspect had been under surveillance for about 18 months after he was identified during an investigation into a French network which sent Islamic radicals to Afghanistan.