Swiss authorities are pursuing a separate investigation into the case of the physicist and suspected al-Qaeda collaborator arrested in France last month.
The Office of the Attorney General of Switzerland opened its investigation at the end of October, according to a spokesman who confirmed a Sunday newspaper report.
The 32-year-old suspect was a researcher connected to but not employed by the European Organization for Nuclear Research (Cern). He also worked at the Federal Institute of Technology in Lausanne.
Cern, a joint project backed by 20 member states, has sites on the border of Switzerland and France. It is best known for the Large Hadron Collider, the world's largest particle accelerator.
Arrested along with his brother - who was released without charge soon afterwards - in the town of Vienne in southeastern France on October 8, the physicist is suspected of being close to al-Qaeda in the Islamic Maghreb (AQIM), also known as al-Qaeda's north African wing. He is a French citizen of Algerian origin.
swissinfo.ch and agencies