Belgian police today arrested 16 people in twin terrorism-related investigations involving Chechen extremists, authorities said.
The suspects belong to two separate groups that had links between them, the federal prosecutor's office said.
Members of one group, based in western Flanders, were allegedly active in Syria and probably participated in combat there, prosecutors said.
One group member returned home to Belgium for medical care after being wounded while fighting with an extremist Muslim faction, authorities said. Some of those arrested allegedly had plans to return to Syria.
The other group, in the Leuven region, had been under investigation since January for possible involvement in preparing an attack, the prosecutor's office said.
Authorities also performed simultaneous searches in the Belgian cities of Ostende, Bredene, Antwerp, Jabekke, Leuven and Namur, the prosecutor's office said.
Belgium has been among the European countries most seriously affected by the departure of young people to fight with IS and other extremist groups in Syria and Iraq.
There are fears that the combatants will inspire attacks in their home countries, or engage in attacks themselves when they come home. On Jan. 15, Belgian counterterrorism units foiled what was described as a jihadi plot to mount a major attack, killing two gunmen and wounding a third in the eastern city of Verviers near the German border.
Reacting to today's arrests, Prime Minister Charles Michel hailed the work of the country's police and prosecutors in "combating terrorism without pause."
"We will never leave the smallest place in our democracy for all these people who represent a veritable menace for our fellow citizens," Michel said.
