The government meanwhile came in for a torrent of criticism, with key ministers on the back foot saying they had done everything possible to prevent Tuesday’s airport and metro attacks which left 31 dead and some 300 wounded.
The Belgian government has been accused of failing to stop countrymen from joining Islamic State in Syria from where they return home battle-hardened and more extremist than before.
On Friday, a series of raids produced three arrests in connection with what French authorities said was an imminent new attack.
French President Francois Hollande said a jihadist network which hit both Paris and Brussels was being 'destroyed' but also warned that the threat remained and everyone must be on guard.
The Belgian government has admitted to 'errors' and two ministers offered to resign after Turkey said it had arrested and deported Ibrahim El Bakraoui, who blew himself up in the airport attack.
A huge manhunt is still under way for at least two suspects -- one of the airport attackers whose bomb failed to go off and another man seen in the metro with Khalid El Bakraoui just before he detonated his bomb.
Investigators also say Khalid rented an apartment in Brussels used by Salah Abdeslam, who was arrested in the Belgian capital on March 18.
Meanwhile, grieving Belgians continued to gather in a central Brussels square carpeted with flowers and tributes to the dead and wounded as the country tries to come to terms with the tragedy.
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Suspect arrested in Belgium is not bomb-maker Najim Laachraoui