Four European leaders paid homage to the victims of the attack at the Jewish Museum in Brussels on Tuesday.
Four people, an Israeli couple, a French woman and a Belgian employee of the museum were killed by a gunman who is still at large.
French President Francois Hollande, Italian Prime Minister Matteo Renzi, Belgian Prime Minister Elio Di Rupo and European Parliament President Martin Schulz met the Museum director Philippe Blondin at the entrance of the building where anonyms continue every day to lay flowers and light memorial candles.
The European leaders, who were meeting in Brussels to attended an EU informal summit and assess the results of the EU elections, bowed their heads as Rabbi Levi Matusof from Paris recited a prayer for the dead.
Belgium investigators are still probing a terrorist link in the shooting by a lone gunman that has shocked the world.
The attack -- carried out in cold-blood by a "well-prepared" killer, according to police and video image.
It was the first for more than 30 years in Belgium and has revived fears of a return of violent anti-Semitism to Europe.
Belgian authorities have denied tv reports that they have arrested a suspect in the attack.
Belgian tv station VTM reported that authorities were questioning a suspect who was arrested in connection with another case over the shooting but a Belgian official later said the report was false.
The museum, located in the center of Brussels, was expected to reopen Tuesday but it will remain closed for the purpose of the investigation.
The museum is one of the few Jewish institutions in Brussels that is not under permanent police protection.
A memorial service for the victims will be held next Monday at the Great Synagogue of Brussels.