Kurdish-led forces in northern Syria on Thursday announced the capture of French jihadist Adrien Guihal, known as the voice that claimed 2016 attacks in France for the Islamic State group.
"The SDF's intelligence services conducted an operation on May 19 that led to the capture of a group of IS jihadists led by Adrien Guihal, known as Abu Osama al-Faransi," the Syrian Democratic Forces said in a statement.
Guihal was thought to be among the most dangerous members of the large French contingent in the ranks of the Islamic State group, whose self-styled "caliphate" spanned huge swathes of territory in Iraq and Syria before collapsing last year.
The Kurdish forces controlling northeastern Syria have detained dozens of French IS members who have gone underground in recent months, including well-known figures such as Thomas Barnouin and Emilie Konig.
The SDF statement said Guihal was detained together with his wife, who was not identified, in the area of Raqa, IS's former Syrian "capital" which the US-backed SDF took last year.
He made headlines when he was recognised as the man behind the voice that claimed responsibility for the July 2016 attack that killed 86 people in the French city of Nice.
He is a veteran member of France's jihadist networks however.
- Uncertain fate -
He converted to Islam while he was still in his teens and became acquainted with the brothers Fabien and Jean-Michel Clain, central figures in French jihadist circles, more than 10 years ago.
According to a profile in French daily Liberation, Guihal learnt Arabic in Cairo and became very active in online jihadist forums.
He was detained in France in 2008 on charges of planning an attack in France to protest against the French military presence in Afghanistan and was sentenced in 2012 to four years in prison.
He was released that same year.
According to Liberation, he immediately started forming another jihadist cell in the Paris region and eventually managed to reach Syria in the spring of 2015.
IS conquered swathes of Syria in 2014 and eventually proclaimed a "caliphate" about the size of Britain after taking Iraq's second city of Mosul and overrunning vast expanses of territory in both countries.
Hundreds of jihadists, including converts like Guihal, streamed into the pro-state headed by Abu Bakr al-Baghdadi.
Around 300 French jihadists, including at least 12 women, have been killed in Iraq and Syria, according to French security and other sources speaking to AFP in March this year.
Another 40 or more French nationals are being held by held by the SDF and their fate is a controversial issue in France, whose authorities seem reluctant to bring them home for trial.
France argues that any adults among them should be tried where they are, so long as they face a "fair trial".
Rights groups and lawyers for the families of the jihadists say none of them are getting due process in the Kurdish-run part of Syria.
There is also some concern that the Kurds, who feel they have been abandoned by their erstwhile Western allies since the collapse of the IS "caliphate", might let dozens of dangerous loose if their home countries refuse to repatriate them.