A senior French intelligence source told Israel Hayom on Monday that he estimates there are at least 20 jihadist terrorists currently in Europe who are potentially just as dangerous and as willing to kill as the shooter who murdered three people at the Jewish Museum in Brussels recently.
Meanwhile, French media revealed new details about the Brussels shooter, 29-year-old Mehdi Nemmouche, who was apprehended in Marseilles last Friday during a routine customs check. It was reported that during a previous stint in prison, Nemmouche was held in solitary confinement for a year because of the religious radicalization he had undergone.
In addition, during the manhunt for Mohammed Merah, the terrorist who shot and killed three children and their teacher at the Ozar Hatorah Jewish day school in Toulouse in 2012, Nemmouche asked his prison guards for a television so he could follow the developments.
While Nemmouche has given his interrogators plenty of information about his past and his Islamist radicalization, he has yet to provide answers about the Jewish Museum shooting, which has left the door open for speculation that he may not be the shooter and that the terrorist attack was a professional assassination. French police arrested four other people on Monday in a sweep against jihadist recruiters.
Also on Monday, a delegation of 38 representatives of the World Jewish Congress, headed by Ronald Lauder, arrived in Belgium to grieve with the Jewish community. The delegation met with Belgian Prime Minister Elio Di Rupo, as well as the justice and interior ministers. Meanwhile, the mayor of Antwerp, Bart De Wever, called on the military to station soldiers at Jewish institutions to provide protection.
In Israel, Prime Minister Benjamin Netanyahu addressed the Brussels terrorist attack during a meeting of the Knesset Foreign Affairs and Defense Committee.
"Islamist terrorism is rearing its head in Europe. It is strange in my eyes that European governments speak about friendship with a Hamas unity government that commits these very same acts and glorifies them," Netanyahu said.
Meanwhile, between 1,000 and 1,500 Europeans may currently be fighting in Syria against President Bashar Assad, according to Charles Lister, an analyst with Brookings Doha Center, who drew the estimate from governments and other sources.
A leading French criminologist who advised former French President Nicolas Sarkozy said that a lack of coordination and data sharing among nations -- even within the EU -- was stymieing measures to counter the threat.
"The task is not impossible," said Alain Bauer. "You need greater and better coordination."
A major issue, he said, is that in sharing information "you also share some intelligence about who gave you the information. Protecting a source is a major problem."
Bauer underscored the importance of catching potential terrorists before they could travel to their destinations. This means "early intelligence, early warning, early detection. That is something we don't do," he said.