On July 31, the left-wing newspaper Liberation floated on its front page the idea that Ligue de Défense Juive (LDJ), the group that played a key role in defending Don Isaac Abravanel Synagogue in central Paris when it was attacked by a Muslim mob on July 13, should be banned.

According to other liberal or left-wing media outlets, the French Interior Ministry "was about" to issue such a ban.

Joel Mergui, the chairman of Consistoire (the National Union of French synagogues), retorted in a TV interview: "Why not ban the organisers and sponsors of antisemitic demonstrations and those dozens of mosques that incite people to anti-Jewish hatred and violence? It is the Jews who are under attack in France, not the opposite."

Although no incriminating evidence against LDJ was found, officials at the Interior Ministry and the left-wing press insisted that the Jewish organisation should be dissolved.

Many observers think the socialist François Hollande administration and senior police officers want to emphasise extremism on both sides - among "rogue Jews" as well as among Muslims.

"It is the Hollande administration's major conundrum," one pollster said. "Mr Hollande and Prime Minister Manuel Valls have expessed pro-Jewish and even pro-Israel views. But 86 per cent of French Muslims voted for them in 2012 and were instrumental in their relatively narrow victory over Nicolas Sarkozy. They have to retain the Muslim vote in order to survive politically."