Manuel Valls
Manuel VallsReuters

France's prime minister on Sunday defended a controversial decision to ban a pro-Palestinian demonstration in Paris that went ahead anyway and degenerated into violence.

The rally Saturday in a northern district of the French capital was initially peaceful, but scores of men later clashed with riot police, throwing stones and bottles at security forces who responded with tear gas, sending locals and tourists running for shelter.

Police – 17 of whom were injured – detained 44 people over the violence and on Sunday 19 of were still being held.

"What happened again yesterday in Paris – unacceptable unrest – justifies all the more the brave choice by the interior ministry to ban a demonstration," Prime Minister Manuel Valls said Sunday.

The decision to ban Saturday's demonstration was taken out of fear that the Jewish community would be targeted after protesters last weekend tried to storm two synagogues in Paris during a similar rally.

But the move was met with controversy, particularly after protests that were allowed to take place Saturday in other cities went ahead peacefully.

The Israeli counter-terror offensive in Gaza has stoked passions in France – which has the largest Muslim population in western Europe as well as a 500,000-strong Jewish community.

It has highlighted divisions within French society – a Jewish community increasingly concerned over anti-Semitism, French people of north African descent who include a growing radical Islamic fringe, and far-left activists whose opposition to Israeli policies sometimes verges on anti-Semitism.

Speaking as he commemorated the anniversary of the Vel' d'Hiv Roundup – a mass arrest of Jews in Paris on July 16 and 17, 1942, which was followed by their deportation to the Nazi death camps – Valls warned of "a new form of anti-Semitism".

He said it was spreading "on the Internet, on networks, in working class areas, among young people who are often aimless, who have no awareness of history, who hide their 'hatred of the Jews' behind the facade of anti-Zionism and behind hatred of the Israeli state."