Former French President Nicolas Sarkozy has been taken into police custody for questioning over allegations that he received campaign funding from the late Libyan leader Col Muammar Gaddafi.
Police are investigating alleged irregularities over the financing of his 2007 presidential campaign.
Police have questioned him previously as part of the probe. Mr Sarkozy has denied any wrongdoing.
The centre-right politician failed to return to power in 2012.
Judicial sources said he was being questioned in Nanterre, a suburb in western Paris.
In 2013, France opened an investigation into allegations that his campaign had benefited from illicit funds from Gaddafi.
The sources said one of Mr Sarkozy’s former ministers and a close ally, Brice Hortefeux, was also being questioned by police on Tuesday.
A former aide, Alexandre Djouhri, is fighting extradition to France after being arrested in London in January on suspicion of money laundering as part of the case.
The Swiss businessman has denied the allegation and says the investigation is politically motivated.
The claims about funding from Gaddafi came from a French-Lebanese businessman, Ziad Takieddine, and some former Gaddafi regime officials.
He can be held and questioned by police for up to 48 hours. Then he may appear before a judge and may face charges.
French media say it is the first time that police have detained him over the Libya allegations.
But he was detained in 2014 in a separate investigation into alleged campaign funding abuses – the first time this has happened to a French ex-president.