Four people arrested in Belgium on Friday in raids aimed at smashing jihadist recruitment groups have been charged with "participating in the activities of a terrorist group", the federal prosecutor's office said.
The four suspects picked up in a nationwide swoop involving around 170 police were remanded in custody after appearing before an investigating magistrate, the prosecutor's office added.
Their identities were not disclosed.
The raids on 22 locations, mainly in the eastern Limburg province, close to the border with the Netherlands, turned up no weapons.
"This case concerns people who want to go to Syria and fight there," the prosecutor's office said.
The prosecutor said the operation was not related to a January 15 shootout between police and jihadists in the Belgian town of Verviers, in which two suspected militants were shot dead.
Meanwhile, one of two Belgians arrested in France a day after the Verviers shootout was handed over to Belgian authorities Friday, the Belga agency reported.
The man identified as Ismael El Abdi, 32, was also charged with participating in the activities of a terrorist group and taken into custody, the reported cited the prosecutor's office as saying.
His younger brother, who was arrested with him, has taken a court case opposing his transfer to his homeland.
Belgium has been on high alert since the January 15 uncovering of a cell that was plotting attacks on police on the street and in stations.
The group's suspected mastermind -- Abdelhamid Abaaoud, a Belgian jihadist who allegedly fought alongside the Islamic State group in Syria -- is still at large.