Part of the investigations around the case also saw former Liverpool striker Djibril Cisse taken into custody and later released.
The prosecutor has placed Benzema under formal criminal investigation, with a source close to the case saying: "We can confirm that he is being questioned over his role in this affair".
Benzema can be held and questioned for up to 48 hours, but his lawyer, Sylvain Cormier, says the striker is relaxed as he did nothing wrong
"He came to respond to some questions. He is fine. He had nothing to do with this blackmail case. "He's pleased, even satisfied, that he can end this controversy once and for all".the lawyer said.
Earlier this year, Karim Benzema was cleared of underage sex charges in France.