The former French President, Nicolas Sarkozy, has been charged with corruption and illegally using his influence after a day in custody.
The disgraced politician was questioned by police for 15 hours, Le Monde reported, and was left without a lawyer when Thierry Herzog was also arrested along with two senior judges.
Mr Sarkozy, 59, has become the first former French President taken into custody in a criminal investigation, making his widely anticipated political comeback look ever more unlikely.
The right-wing leader has been accused of multiple illegal dealings, mostly linked to the financing of his 2007 and 2012 election campaigns.
Video: Nicolas Sarkozy charged with corruption
According to prosecutors, he has been charged with corruption, “influence peddling” and concealing breaches of confidentiality.
He had turned himself in at the police headquarters in Nanterre, outside Paris, on Tuesday morning and was placed under arrest.
Mr Sarkozy and his lawyer are suspected of illegally cultivating a network of informants within France’s top court, the Cour de Cassation, and the police.
He is accused of promising one of the magistrates, Gilbert Azibert, a prestigious job in Monaco in return for information that could help his defence in a case in which he was accused of soliciting money from L’Oréal heiress Liliane Bettencourt.
The preliminary criminal charges against Mr Sarkozy in that case were dropped by a Bordeaux court last October.
The latest charges came to light when police tapped his phone while investigating allegations he sought €50 million from toppled Libyan leader Muammar Gaddafi, for his 2007 election campaign.
Mr Sarkozy, his lawyer and the magistrates deny all charges but the former President could face 10 years in prison if convicted.