Jihadists have executed four Nigerian hostages held since July, French aid group Action Against Hunger said, adding that one of its staff and two drivers were among those killed.
The 40 radicalized prisoners who are preparing to leave French prisons over the next 18 months after serving their sentences are "a major risk", France's leading counter-terrorism prosecutor has warned.
The French government said on Friday said it would seal off extremists within prisons and open new centres to reintegrate returning jihadists into society as part of a new plan to halt the spread of radical Islam.
How should France deal with its scores of radicalized prisoners? A new report has criticized the scheme of housing them together separate from other prisoners.
Prime Minister Manuel Valls said extreme forms of Islam were winning the propaganda war for hearts and minds, warning the
veil was being used as a political symbol for the "enslavement of women".
A jihadist group repeated its call for attacks on French soil as well as the assassination of President François Hollande in revenge for the European nation's recent interventions in Africa, terrorist monitoring group SITE said on Sunday.
France has withdrawn its first batch of soldiers from Mali, the army said on Tuesday, as it begins to pull out troops sent to battle Islamist fighters in the west African nation.
Mali's sovereignty over almost all of its territory will be restored within "a few days", French President Francois Hollande promised as French troops prepare to pull out.
A French corporal was killed tracking down jihadist fighters in their northern Mali mountain bastions, bringing to five the number of French deaths since Paris launched a military offensive in the country two months ago.
French Defence Minister Jean-Yves Le Drian has visited French troops in northern Mali, where the military says they have killed 150 Islamist rebels over the past month.
A French-Malian citizen arrested in November for allegedly seeking to join Islamist militants in Mali has been expelled to France where he will be held for questioning, a French judicial source said on Thursday.
Islamist gunmen attacked the largest city in northern Mali on Sunday following two straight days of suicide bombings, intensifying their insurgency on territory reclaimed by French-led forces.
France said on Thursday its warplanes had hit Islamist command posts near the last militant stronghold in northern Mali, as the UN mulled a peacekeeping force to take over the fast-moving French-led operation.
France called for peace talks between Mali's government and "legitimate representatives" from the north, after French troops took up positions at Kidal, the last city held by Islamist forces.
French-backed Malian troops wrested two key central towns from Islamist rebels as hostage-takers in neighbouring Algeria said they wanted to negotiate an end to France's military intervention.
The United States will provide transport planes to French forces fighting Islamist militants in Mali but has yet to decide if it will offer refueling tankers for French warplanes, officials said Thursday.
Islamists based in northern Mali, under daily bombardment by France's warplanes, vowed Monday to avenge the assault on French soil as well as in Africa.
France on Friday instructed its citizens to leave Mali following the launch of a government offensive against Islamist forces in the north of the country.
