French Interior Minister Bernard Cazeneuve said police had arrested a suspect in the Paris area today who was in "the advanced stages" of a plot to stage an attack in France.
While Mr Cazeneuve said the raid in the Argenteuil neighbourhood northwest of Paris had led to a "major arrest", he told reporters there was "no tangible evidence linking the plot to either the attacks in Paris or Brussels".
The arrested man, a French national, "is suspected of being involved in the plan at a high level," Mr Cazeneuve said. "He belongs to a terrorist network that sought to strike our country."
Police operations were continuing late tonight, with officers searching an apartment building in Argenteuil after having evacuated its residents.
Bomb disposal experts were at the scene to allow police officers "to proceed with searching the apartment, the parking and the communal areas in optimal conditions," Mr Cazeneuve added.
A security cordon has been set up around the building.
The minister added that the suspect had been under surveillance "for several weeks" and that the arrest was also the result of "close and constant cooperation between European services".
The arrest comes two days after 31 people were killed in suicide bombings at Brussels airport and on the city's metro, putting security services across Europe on high alert.
The assailants in the Brussels attacks - two of whom are still on the run - are known to have had links to those involved in the 13 November Paris attacks that left 130 dead.
Both assaults have been claimed by the so-called Islamic State jihadist group.