France commemorated the fourth anniversary of the Islamic State attacks that struck the heart of Paris with a solemn reading Wednesday of the names of 131 dead, and the growing certainty that the group’s recruits will return home in increasing numbers.

Three squads made up almost entirely of French and Belgian fighters for the Islamic State attacked the country’s national stadium, the Bataclan concert hall, and bars and restaurants in the city center, in the deadliest attack committed by the group in Europe. All but one of the attackers died.

Wednesday’s commemorations of the Nov. 13, 2015, attacks were clouded by the impending return of more European recruits for the Islamic State — many of them women and their children. Turkey’s president has promised to deport foreign supporters of the group, even if their home countries don’t want them.

“These gates will open and these IS members who have started to be sent to you will continue to be sent. Then you can take care of your own problem,” Turkish President Recep Tayyip Erdogan said ahead of a trip to Washington.

Since 2015, Turkey has returned around 250 French citizens, including many children born in Iraq and Syria. Turkey also has an agreement with Belgium, reached after a Belgian former Islamic State fighter linked to the Paris attackers was deported back to Europe and took part in the attacks that devastated Brussels in February 2016.

Laurent Nunez, a ranking official in France’s Interior Ministry, said around 500 people are currently imprisoned on terrorism convictions and that all will be watched closely after they are freed.

But he said the threat remains high for people radicalized at home. “This is the threat we fear most, this homegrown threat that is the most difficult to detect,” he said Wednesday.

Turkey deported citizens of the United States, Denmark and Germany on Monday and announced plans to expel seven other German nationals, two Irish nationals and 11 French nationals. The U.S. national remained in a heavily militarized no man’s land between Turkey and Greece for a third straight day. Greek officials have said Turkey tried to expel the man to Greece, which refused him entry.

France has reluctantly accepted its own returning citizens. Four women are on the verge of being deported from Turkey with their seven children. Among them is Tooba Gondal, a British resident who was dubbed the Islamic State “matchmaker” for recruiting European girls and women to marry fighters, according to Jean-Charles Brisard of the Center for the Analysis of Terrorism. Gondal, who had appealed unsuccessfully to Britain to take her back, has French citizenship.

The French Association for Victims of Terrorism has called for its government to bring Islamic State supporters home.

But public sentiment runs high against the returnees across Europe. Polls show an overwhelming majority want the families — even children — to stay in Iraq and Syria.

Britain has refused to accept anyone and, like Denmark and the Netherlands, has taken the additional step of stripping many of their citizenship. Britain’s policy has been challenged in court, while courts in Germany and Belgium have ordered the government to take back women and children.

Thomas Renard, a researcher with the Egmont Institute in Belgium, said the dilemma was entirely foreseeable almost from the moment hundreds of Europeans started to leave for the war zone in Iraq and Syria.

“Now governments are no longer in a position to decide,” Renard said.

There’s an added element of unpredictability because so many of the surviving European members of Islamic State are women, along with their children, he said. Many of the men died in battle, airstrikes or are in detention in Iraq or Syria.

European countries have slowly ramped up terrorism prosecutions of women who left home to join the group, he said, giving a prison system designed for an overwhelmingly male population little time to adapt.

“It might be that now we’re no longer in this scenario, that it’s not a trickle but it’s a massive return,” Renard said. “I’m not that confident that the system is fully prepared.”

The Japan Times