Prosecutors said Mohamed Abrini admitted to being the "man in the hat" seen on Brussels airport CCTV with the bombers.
Officials had double counted three people with dual nationality.
“If we are able to be together, then the terrorists have failed.”
Belgian media say one is the man captured on CCTV in Brussels airport.
Belgian authorities found a highly volatile explosive, nicknamed "Mother of Satan," at an apartment used by the attackers.
After the vigils to mourn and honor those who perished today, we must commit anew to making our world not only safe but whole and to creating communities that cross lines of difference, rather than remain entrenched in sameness.
The deadly attacks on Tuesday follow months of tensions, and warnings.
Alphonse Lyoura pulled six or seven wounded people to safety.