Court artist's drawing of Mehdi Nemmouche during his murder trial
Court artist's drawing of Mehdi Nemmouche during his murder trialREUTERS

French jihadi terrorist Mehdi Nemmouche was found guilty Thursday of the "terrorist murders" of four people at Brussels' Jewish museum, the first case of a Syria jihad veteran to stage an attack in Europe.

Nemmouche, 33, sporting a trimmed beard and wearing a navy blue sweater, showed no emotion and stared into space as the verdict was delivered.

He now faces a life sentence for the anti-Semitic attack in the Belgian capital on May 24, 2014, following his return from Syria's battlefields.

Sentencing could be as early as Friday.

The 12 jurors, accompanied by the presiding judge and two other magistrates, had deliberated for more than two days in secret at a Brussels hotel before returning their verdict.

Nemmouche was found to have killed the four victims in cold blood in less than 90 seconds, but he denied the accusation telling the court he had been "tricked".

This referred to arguments made by defense lawyers that Nemmouche was not to blame for the cold-blooded slaughter, but that he was caught up in some kind of plot targeting the Israeli intelligence agency Mossad.

The legal argument had centered around Israeli couple Miriam and Emmanuel Riva, the first two of the four people killed in the attack.

A young Belgian employee, Alexandre Strens, and French volunteer Dominique Sabrier were also murdered.

According to the defense, the museum shooting was not the work of the Islamic State group but a "targeted execution" aimed at Mossad agents.

The defense said the Israeli couple who were killed were in fact Mossad agents murdered by another man who had hunted them down.

The Riva family's lawyers have furiously rejected the theory and said attempts to pass off the tourists as secret agents was "an absolute scandal".

"Let's stop the joking," prosecutor Yves Moreau told the court earlier this week, describing the arguments presented by the defense as "complete nonsense" against compelling evidence.

Miriam Riva worked for Mossad but, as an accountant, she was not operational, said the investigating judges who travelled to Israel during their investigation.

- 'Deeply convinced' -

Yohan Benizri, the head of Belgium's Coordinating Committee of Jewish Organisations, denounced what he called a "nauseating conspiracy theory".

The 12 jurors also found fellow Frenchman Nacer Bendrer, 30, who was accused of supplying the weapons, to be the co-author of the attack.

The investigation showed that the two men had dozens of telephone conversations in April 2014, when Nemmouche was preparing for the killings.

Six days after the massacre, Nemmouche was arrested in the French city of Marseille in possession of a revolver and a Kalashnikov-type assault rifle.

At the trial, Bendrer admitted that Nemmouche had asked him for a Kalashnikov when he came to Brussels in early April, but claimed he never delivered it.

Among other personal effects, Nemmouche upon arrest carried a nylon jacket with gunshot residue, as well as a computer in which investigators found six videos claiming the attack with an off-camera voiceover thought to be Nemmouche.

In total, the prosecution said it had identified 23 pieces of evidence pointing to Nemmouche, who also physically resembles the shooter seen on the museum's surveillance video.

"We are both deeply convinced that the two accused did indeed commit these acts," one of the two prosecutors said in their indictment.

The prosecutors say the attack was the first carried out in Europe by a jihadist returning from fighting in Syria.

The Brussels killings came 18 months before the November 13, 2015, Paris attacks which left 130 dead.