The trial opened Thursday of a Frenchman accused of shooting four people dead at a Jewish museum in Brussels, allegedly the first Syria jihad veteran to stage a terror attack in Europe.
Mehdi Nemmouche, 33, who was in court, faces a life sentence if convicted of the killings in the Belgian capital on 24 May 2014, following his return from Syria's battlefields.
Both Nemmouche and Nacer Bendrer, a fellow Frenchman aged 30 who allegedly supplied the weapons, are due to hear the 200-page charge sheet against them in the first two days of the trial being held in a Brussels criminal court under heavy security.
Accompanied by two masked police officers, Nemmouche sat down in the dock wearing an orange sweater. He gave his name upon the request of the chief judge.
Bendrer, who could also be jailed for life if convicted, was also in the dock.
Both have previously denied charges of "terrorist murder" for the anti-Semitic 82-second shooting spree.
More than 100 witnesses are due to testify at the trial which is being attended by the victims' families and Jewish community leaders.
Firing a pistol and then an assault rifle, the gunman killed two Israeli tourists, a French volunteer and a Belgian receptionist at the Jewish Museum.
Nemmouche -- born to a family of Algerian origin in the northern French town of Roubaix -- was arrested six days after the attack in the southern French port city of Marseille after arriving on a bus from Brussels.
Investigators say he was carrying a handgun and an assault rifle used in the shooting.
They say he fought with a jihadist faction in Syria from 2013 to 2014, where he met Najim Laachraoui, a member of the gang which went on to carry out suicide bombings in Brussels that killed 32 people in March 2016.
The same Brussels cell is also alleged to have coordinated and sent jihadists to carry out the Paris gun attacks and bombings on 13 November 2015, in which 130 people were killed and hundreds more wounded.
Both attacks were claimed by the Islamic State (IS) group, whose activities in Syria and Iraq lured thousands of jihadists from Europe.
Nemmouche and Bendrer, investigators say, met nearly a decade ago while in prison in southern France, where they were both described as "radicalised" inmates who tried to win others over.
Bendrer was arrested in Marseille seven months after the Jewish Museum attack and charged as Nemmouche's accomplice.
Although he was jailed for five years in September by a French court for attempted extortion, he was transferred to Belgium for the trial.
Nemmouche is expected to face a separate trial in France for holding French journalists hostage in Syria.
The former hostages are expected to testify about Nemmouche's character during the Brussels trial, despite the defence arguing that theirs is a separate case.
More than 300 Belgian and foreign journalists have registered to cover the museum attack trial which could last until the end of February.