The European Commission has said it has not been told of any specific threat against it from possible Jihadist fighters returning from Syria.
There had been reports that the EU headquarters in Brussels was a target for jihadists.
Belgian authorities yesterday confirmed they had made several arrests.
There was no visible increase in external security around the Commission headquarters in the European Union district of central Brussels today.
A spokesman for the federal judicial office in Brussels said he could not comment on the matter.
Dutch public broadcaster NOS said at least two people among those arrested in the Belgian operations came from The Hague.
NOS said one possible target was the Commission building.
It said the aim had been to kill as many people as possible, similar to an attack in May on the Jewish museum in central Brussels which left four people dead.
The Commission is the public face of the European Union and it has one of the most high-profile buildings in Brussels.
The building houses several thousand officials and the top brass in charge of the daily running of the 28-nation bloc.
Brussels is also home to NATO's headquarters and many other international companies and organisations, but security is mostly low-key and discreet.
Belgium, like several European countries, is increasingly worried about its nationals going to fight in Syria and Iraq.
They fear they will return home battle-hardened and even more radicalised, posing a threat to security.
It is estimated 400 Belgians may have travelled to Syria or Iraq, while about 90 have returned home.
