A freed French hostage has said the terrorist behind the deadly shooting at the Jewish Museum in Brussels in May was among his Islamic extremist captors in Syria, and was part of the Islamic State (IS, formerly ISIS) terror group.
Writing on the website of his former employer Le Point magazine, Nicolas Henin said Mehdi Nemmouche, who has been extradited to Belgium and held for questioning, was his jailer between July and December 2013.
One of a group of four journalist hostages freed in April, Henin said the 29-year-old, who spent more than a year fighting in Syria, was a feared and violent figure.
"When Nemmouche was not singing, he was torturing," wrote Henin. "He was part of a small group of Frenchmen whose visits would terrify the 50-odd Syrian prisoners held in the cells nearby."
"Every night the blows would start raining down in the room, where I was also interrogated. The torture lasted all night, until dawn prayers."
Interior Minister Bernard Cazeneuve confirmed that French intelligence services had "transferred elements to the judiciary that suggest (Nemmouche) may have been the jailer of our hostages," following a report in Le Monde newspaper.
A police source told AFP the freed hostages had recognized Nemmouche from photographs following his arrest.
Le Point said that Henin had kept quiet on Nemmouche's role in his detention to protect the Western hostages still being held by Islamic State terrorists, but decided to speak out following Le Monde's report.
Henin's lawyer Marie-Laure Ingouf told AFP that "Nemmouche was one of his jailers. All the hostages confirm this. They lived alongside him for several months."
The Frenchman of Algerian descent was remanded in custody in early August on charges of "murder in a terrorist context" over the May 24 shooting, which left four dead.
He is slated to appear on September 12 before a Brussels judge who will decide whether to extend his preventive detention.
The attack in broad daylight left an Israeli couple, a Frenchwoman and a Belgian man dead, and raised fears of terror attacks from foreign fighters returning from Syria.
Nemmouche was arrested in the southern French city of Marseille days afterwards.
He has been sentenced seven times in France, including for armed robbery, and has spent seven years in jail where he was notably found proselytizing Islam.
Henin in Le Point described Nemmouche as "a self-centred fantasist for whom jihad was finally an excuse to satisfy his morbid thirst for notoriety. A young man lost and perverse."
"He probably didn't join the Syria fight for some ideal, but above all due to a lack of recognition," echoed the journalist at a press conference.
Speaking after the four journalists' release, French Foreign Minister Laurent Fabius said some of their captors spoke French. Western Governments have said hundreds of Westerners have joined extremist groups in Syria.
That point was illustrated in the recent brutal beheading of American journalists James Foley and Steven Sotloff, both of whom Henin says he was held captive together with for a period of time. The two were beheaded by an Islamic State (IS, formerly ISIS) terrorist from England.