Belgian police on Thursday arrested seven people suspected of supporting the Islamic State group and plotting a "terrorist attack," prosecutors said.
Almost all of the suspects are ethnic Chechens, and three of them possess Belgian nationality, prosecutors said in a statement.
"The exact target of the planned attack has not yet been determined," they said.
Police, backed by elite units, raided nine addresses in several towns in western Belgium in an operation led by an investigating judge who specializes in terrorism cases.
The judge will decide later if there is sufficient evidence to charge the suspects, the statement said. "Possible charges are attempted terrorist assassination, participation in the activities of a terrorist group and preparation of a terrorist attack," it said.
Prosecutors added that all seven arrested "are suspected of preparing a terrorist attack in Belgium." They all "belong to a group of strong supporters of the IS."
A spokesman for the federal prosecutors office, Eric Van Duyse, told AFP that "they apparently intended to target an institution located in Belgium" and had been "actively searching for weapons."
The police raids took place in Ghent and the smaller towns of Roeselare, Menen, Ostend and Wevelgem.
The Islamic State group claimed responsibility for suicide bombings in Belgium on March 22, 2016, that targeted Brussels' airport and the capital's metro, killing 32 people and wounding hundreds.
Those bombings occurred months after the November 2015 attacks in Paris that were planned by the same IS cell and that killed 130 people.
Chechnya, a republic in Russia's North Caucasus region, has a predominantly Muslim population.
It is ruled by pro-Kremlin strongman Ramzan Kadyrov, who supports Russian President Vladimir Putin's war in Ukraine and who has sent his militia there to fight.
