A French Islamist arrested in northern Mali arrived in Paris and was handed over to the DCRI intelligence agency for questioning, the source said.
Gilles Le Guen, 58, who goes by the name Abdel Jelil, was detained by French forces near Timbuktu in April. He is believed to have joined the north African militant organisation Al-Qaeda in the Islamic Maghreb (AQIM) after moving to Mali with his family.
"He will be questioned. We want to know the path he has taken," Interior Minister Manuel Valls said on Europe 1 radio.
In October, Le Guen appeared in Islamic dress with a gun at his side in a video on a Mauritanian website in which he warned France, the United States and the United Nations against military intervention in Mali to drive Islamists from the country's arid north.
France went on to launch and lead an operation in January to halt an advance by extremists on Bamako and drive them from Mali's northern cities which they had controlled for about nine months.
Le Guen was held prisoner by AQIM for several days in November 2012 and some sources say the group believed he was a spy while others say AQIM picked him up after he intervened to stop Islamists from mistreating women.
Le Guen's Moroccan-born wife and their five children were flown to France two weeks ago.