They called him Papa Noel — Father Christmas — and not only because of his thick beard and stocky build.
He was also the generous sort, providing advice, logistical aid and travel expenses to his proteges — mostly young Belgians of Moroccan descent harboring an identity-affirming, if potentially fatal, obsession: to go off to Syria for jihad.
That fateful journey became a rite of passage for scores of disaffected youth in the Belgian capital's working-class Molenbeek district, just across an old industrial canal from downtown's shabby-chic beer joints and trendy cafes.
Molenbeek, now notorious worldwide as a launchpad for young Belgians who ventured off to Syria and were killed or returned home to wreak havoc, is where this pseudo-Santa, Khalid Zerkani, plied his trade.
Last week's attacks on the airport and metro in Brussels — along with revelations of a foiled terrorist strike in France — have focused renewed public attention on Belgian-based militant recruiting networks and the singular case of Zerkani, now serving a 12-year prison term for his enlistment efforts. Belgian authorities have labeled the radical but charismatic preacher the nation's most proficient recruiter of extremist foot soldiers.
"Mr. Zerkani has corrupted an entire group of youth from Molenbeek," a Belgian federal prosecutor, Bernard Michel, said in February, urging that the court increase his sentence to 15 years.
Last week, a former Zerkani confederate, Reda Kriket, was arrested outside Paris in connection with what authorities called a plot in "advanced stages" to attack France. Kriket, 34, a.k.a. "The Frenchman," had been convicted last year in absentia of being an operative in Zerkani's Belgian jihadist pipeline.
"He was part of a terrorist network that planned to strike France," French Interior Minister Bernard Cazeneuve said on Thursday of Kriket, a former resident of the Brussels district of Ixelles.
Zerkani's case, and a separate prosecution of members of a now-disbanded militant group called Sharia4Belgium, put a spotlight on the underground recruiting networks that helped make Belgium a focal point for Syria-bound militants and a hub for both last week's attacks in Belgium and November's strikes on Paris.
About 500 Belgians have traveled to Syria to join militant factions, according to various estimates, the largest per-capita representation among any European nation.
The extent and brazenness of the recruiting process highlighted how Belgian authorities were slow to recognize the threat. After last week's bombings, Belgium officials have come under withering criticism for not having done more to prevent attacks arising from homegrown militants. Two Cabinet ministers offered to resign, acknowledging that mistakes had been made in the run-up to last week's attacks.
"We thought for too long that rationality would prevail over madness," said professor Brice De Ruyver, director of the Institute for International Research on Criminal Policy at the University of Ghent. "We thought it would stay limited to only a few. And we have severely underestimated the recruiting power of a few hate preachers and people who rally kids with immigrant backgrounds to their cause."
Authorities say the Morocco-born Zerkani, 42, ran his loosely structured operation from underground mosques and other inconspicuous havens in Molenbeek, cultivating petty criminals and other marginalized men and women, occasionally sharing the cash from sundry illicit endeavors. Prosecutors said Zerkani incited his charges to theft and burglary, ripping off cellphones, laptops and cameras in and around Brussels train and bus stations.
"A cynical guru" is how a Belgian court labeled Zerkani last year.
During the trial last year, Zerkani denied that he was involved in violent jihad, insisting that he was a humble believer.
"I'm a pacifist person," he was quoted as saying in courtroom accounts. "I'm not Satan; I don't control what others do."
Belgian authorities began investigating the Zerkani network in 2012, but it took almost two years for police to begin roundups of participants, a delay that led to criticism of Belgium's counter-terrorism efforts. During the two-year period, many Zerkani associates traveled freely between Europe and Syria, testimony showed.
In his heyday, Zerkani was a familiar figure in the gritty Maritime district of Molenbeek, where he would often be surrounded by a clique of admiring young men, according to testimony and press accounts here.
Among his suspected proteges was Abdelhamid Abaaoud, the former Molenbeek resident and suspected ringleader of the Nov. 13 attacks in Paris that left 130 dead. Abaaoud, who appeared in Internet videos while in Syria exhorting fellow French speakers to join the fight, was killed in a police shootout outside Paris on Nov. 18.
He was said to be a high-ranking operative in the external operations branch of Islamic State, the militant group that took responsibility for last week's Brussels attacks and November's mass killings in Paris.
Like Kriket, Abaaoud was convicted in absentia of terrorism-related charges in July in the broad Belgian prosecution targeting Zerkani's recruiting web. According to testimony, Abaaoud was one of Zerkani's young followers who helped spread the zeal of jihad around the neighborhood.
A report in De Standaard newspaper on Saturday cited court testimony from Abaaoud's younger brother, Yassine, saying that their mother wasn't keen about her sons hanging around with Zerkani and his associates.
"When my mother learned I had talked to them, she asked me to never do that again," said Yassine Abaaoud, whose shopkeeper family was relatively upscale by Molenbeek standards. "She was afraid of them, called them 'les barbus,'" the younger Abaaoud added, using French slang for "bearded ones," referring to the beards worn by many devout Muslims.
Among the most prominent suspects tried with Zerkani last year was Fatima Aberkan, 55, who took her two teenage daughters to Syria and was dubbed "an exalted muse of jihadist ideology" by the federal prosecutor. Belgian media labeled Aberkan "the mother of Brussels jihad."
One of Aberkan's sons was identified as a recruiter for Zerkani. Another was killed in Syria. She is appealing her conviction and eight-year prison sentence on terrorism-related charges.
"Fatima Aberkan has jihad under the skin," said the prosecutor in the case. "She has sacrificed much for the cause, including one of her sons. For many years, she's contaminated her entourage with her foul and harmful ideas."
Special correspondent Arthur Debruyne contributed to this report.
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