Abdelghani Hadef, who works in a store in Mantes-la-Jolie (Yvelines) was in the process of being deported to his native Algeria on Friday after being arrested on suspicion of leading a jihadist network in France, French daily Le Parisien reported. His lawyer vehemently denies the accusations.
Hadef was arrested by police on Thursday after being tracked for months by France's intelligence services.
On February 10 the Ministry for Economics and Finance ordered Hadef's assets to be frozen on the grounds he was suspected of "promoting armed jihad against France" and of "encouraging violent acts".
He had been held at a detention centre in Vincennes, Val-de-Marne over night on Thursday.
But on Friday Hadef's lawyer Nawel Gafsia discovered that his client had been taken to Charles-de-Gaulle airport in Paris to be deported.
"He was never warned that he would get a notice of deportation. No one told me what was going on. I never saw it," said Gafsia.
"He is being treated like a notorious terrorist even though he has never preached jihad or praised terrorism," his lawyer added.
The move comes just weeks after French authorities expelled another suspected Islamic extremist to his native Morocco.
The interior ministry said Ali Benhamou was expelled to Morocco under an expulsion order following "serious charges" against him.
It linked him with a group known as Forsane Alizza, which was banned in France last year and saw 13 of its members arrested and charged under anti-terrorism laws.
Interior Minister Manuel Valls has also vowed to crackdown on radical Muslim preachers announcing in January that Paris was set to deport a string of extremist imams as part of a fight against "global jihadism".
"Several radical foreign preachers will be expelled in the coming days," Valls told a Brussels conference called to tackle extremism in Europe, without identifying any of the individuals concerned.
"I don't confuse this radical Islam with the Islam of France but there is a religious environment, there are Salafist groupings, who are involved in a political process, whose aim is to monopolize cultural associations and schools," he added.