Police in France have arrested an engineer working at an international nuclear research laboratory on suspicion of having links with an Islamic militant group.
The 32-year-old man of Algerian descent worked at the European Organization for Nuclear Research (CERN) laboratory on the border with Switzerland.
The man and his 25-year-old brother were detained in the south-east town of Vienne on Thursday, the BBC reports.
Police arrested the pair after following internet exchanges between the men and people believed to have links with al-Qaeda in the Islamic Maghreb. French authorities believe the older man was planning attacks in France.
CERN's Large Hadron Collider is aiming to recreate conditions of the Big Bang.
The organisation said the arrested man was not a CERN employee had performed his research under a contract with an outside institute.
It said he was working on a project investigating the slight differences between matter and anti-matter by studying a type of particle called the "beauty quark".