Former French president Nicolas Sarkozy is in custody of financial investigators while being questioned about insider information he allegedly received about a campaign finance probe.
French media say it is the first time a French former head of state has been detained for questioning.
Sarkozy turned himself in Tuesday at a police station in the Paris suburb of Nanterre. The investigation centers on whether he got information illegally on a case exploring whether the late Libyan leader Moammar Gadhafi contributed funds to Sarkozy's 2007 presidential campaign.
Investigators are acting on evidence collected after tapping Sarkozy's phone lines.
Sarkozy has denied any wrongdoing in the case, which is one of several against him that may affect any future run at a return to office. After losing to current president Francois Hollande in 2012, Sarkozy has indicated he may mount another presidential campaign.
Some information for this report was provided by AP, AFP and Reuters.