Former French President Nicolas Sarkozy was summoned Thursday by investigating magistrates as part of a probe into illegal financing of his successful election campaign in 2007, judicial and media sources said.
The former president, who served from 2007 until 2012, appeared before three judges in the south-western city of Bordeaux where the investigation was transferred some time ago.
Sarkozy has not been officially charged with any crime but is being questioned on financing he allegedly received from French billionaire Lilliane Bettencourt, the owner of the L'Oreal cosmetics and luxury products empire.
The judges are investigating the legality of significant contributions by Bettencourt and whether they were properly registered and did not exceed a cap on private contributions to election campaigns.
Media sources also suggested that the contributions may have been solicited and obtained from Bettencourt's company without her knowledge and some of her close advisors have also been investigated.
Sarkozy no longer benefits from presidential immunity and he could be charged if there has been improper conduct. He has denied knowledge of any illicit financing and his former Budget Minister Eric Worth was forced to resign in July 2010 over revelations linked with contacts he had with the Bettencourt empire.
Beyond the financing investigation, media sources also suggested that separate investigations could be imminent concerning Sarkozy's awarding of contracts to pollsters when he was president.
Millions of euros were paid in public contracts to pollsters who regularly rated Sarkozy's performance and there are suggestions these polling agencies were owned by close allies of the former president.
In other potential scandals, Sarkozy is also alleged to have received campaign financing worth Euros 50 million (USD 65 million) from former Libyan leader Moammer Gaddafi, an allegation he strenuously denies.