SARCELLES, France -- Pro-Palestinian French youth defying a ban on a protest against Israel's Gaza offensive clashed with police Sunday, setting fire to cars, pillaging stores and attacking two synagogues in Paris suburbs.
Police, backed by a helicopter overhead, responded with tear gas and shots from non-lethal guns during hours of unrest in the northern suburb of Sarcelles, home to a large Jewish community.
The unrest was the second time in two days that pro-Palestinian demonstrations in France turned violent. The demonstration, like the one in Paris on Saturday, had been banned to ensure peace.
France has Western Europe's largest Muslim and Jewish populations, and crises in the Middle East, like the one triggered by the Gaza offensive, often spill into France.
An umbrella group representing French Jews, known as CRIF, said Sunday night that the Sarcelles synagogue was attacked. The group said that in nearby Garges les Gonesse, Molotov cocktails were thrown at another synagogue, starting a small fire that was quickly extinguished.
CRIF denounced "fanatic groups" behind the attacks and said anti-Semitic violence "is growing by the day."
"It is time to treat it as a 'form of terrorist deviation and treat it as such," the group said in a statement.
The clashes came hours after France honoured some 13,000 Jews rounded up 72 years ago, most kept in a cycling stadium before being sent to Auschwitz.
Prime Minister Manuel Valls denounced a "new form of anti-Semitism" on the Internet that he said was spreading among youth in working-class neighbourhoods.
"France will not allow provocations to feed ... conflicts between communities," Valls said in a speech.
That message was echoed by President Francois Hollande as he decorated Serge and Beate Klarsfeld, who were famous for tracking down old Nazis, as Grand Officer and Commander of the Legion of Honor respectively.
France "will tolerate no act, no words that could give rise to anti-Semitism," Hollande said.
The words by the French leaders were ignored by Sunday's events.
In Sarcelles, several hundred young protesters broke away from a calm pro-Palestinian gathering to riot and clash with police. Some went after the synagogue, CRIF said. Scores of Jewish youth -- some armed with iron bars -- then encircled a synagogue to "protect" it, watched by a cordon of police.
Authorities banned protest marches after a riot in Paris a week ago saw pro-Palestinian youth attacking two synagogues and Jewish stores.
In Paris on Saturday, pro-Palestinian youth burned cars and broke shop windows in a neighbourhood dominated by immigrants.
