The police anti-terrorist raid took place in Brussels, eastern Liège province and in Flemish-speaking Brabant, central Belgium, on Sunday and Monday.
Six people were detained during the operation. Four were later released.
Two of the suspects were arrested. According to prosecutors, they did not have a direct connection with the Paris attacks in November that killed 130 people.
Earlier, the Dutch-language Nieuwsblad newspaper reported that police fear that the attacks might take place near Grand Place, the central square of Brussels. which attracts scores of tourists every day.
Belgium has been on high alert in recent months. Brussels, especially its troubled Molenbeek neighborhood, has been at the center of an investigation into the Paris attacks, as several of the assailants came from Belgium, and one of the suspected attackers is believed to have returned there.
Belgian prosecutors arrest 2 suspected of plotting attacks in Brussels
29 December 2015
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The suspects were reportedly planning to organize attacks in "emblematic places" in the Belgian capital, the prosecutor added, as cited by RTL.
