BRUSSELS — A French citizen suspected of working for the Islamic State in Syria was convicted Thursday of murdering four people at a Jewish museum in Belgium’s capital, an attack that crystallized fears in Europe that foreign fighters would return to sow terror at home.
Reading out the jury verdict at the Brussels criminal court, presiding Judge Laurence Massart, said the defendant, Mehdi Nemmouche, was guilty of four “terrorist murders” in the killing of an Israeli couple and two museum employees on May 24, 2014.
Mr. Nemmouche, 33, sat impassively while the verdict was read, three police officers wearing ski masks surrounding him. He faces up to 30 years in prison at a sentencing hearing set for Monday.
Another defendant, Nacer Bendrer, was found “guilty beyond all reasonable doubt” of supplying the revolver and assault rifle used in the killings. Mr. Bendrer, 30, sat with his head bowed during the reading of the verdicts.
Defense lawyers had argued the killings were part of a conspiracy and Mr. Nemmouche was set up by security officials — perhaps from Iran or Lebanon — who shot the couple because the Israelis might have been members of Mossad, Israel’s intelligence service.
Security camera video from the Jewish museum’s entrance showed a man wearing a baseball cap and armed with a revolver shoot the man and woman in the back of the head at point-blank range.
He then walked down a corridor and fired into offices at the two other victims, before pulling out an assault rifle to spray the area. It was over in 82 seconds and the killer strode away without looking back.
Mr. Nemmouche, who prosecutors claim fought alongside Islamic State extremists in Syria, was captured in France almost a week later in possession of the weapons used in the killing.
French authorities also allege he was one of the jihadists who kept four French journalists hostage until they were freed in April 2014 in Syria. Mr. Nemmouche still must face charges in France linked to the hostage-taking.