Paris ? Gendarmes mingled with shoppers and tourists on Paris’ famed Champs-Elysees Saturday, stopping some passers-by to check IDs, as riot police stood by on the capital’s grandest avenue.

Thousands more police guarded the Eiffel Tower, train stations and other famed sites as part of emergency measures enacted in response to text messages and Internet blog postings calling for “violent actions” in Paris on Saturday evening. Authorities banned public gatherings considered risky in an effort to keep the unrest that has stretched across France for 17 days from reaching inside the capital.

“This is not a rumor,” National Police Chief Michel Gaudin said, citing Paris’ best-known landmarks among potential targets. “One can easily imagine the places where we must be highly vigilant.”

But in Lyon, France’s third largest city, police fired tear gas to disperse stone-hurling youths at the historic Place Bellecour. It was the first time since the unrest began that youths clashed with police in a major city.

More blazes

In separate incidents Saturday night in the southern city of Carpentras, rioters rammed burning cars into the side of a retirement home and a school. A second school and linen store were also set ablaze there.

The violence started in the Parisian suburb of Clichy-sous-Bois on Oct. 27 when about 100 youths rioted to protest the accidental deaths of two Muslim teens who were electrocuted while hiding from police in an electricity substation.

The turmoil, marked by arson and clashes with police, quickly spread across France in housing projects plagued by unemployment and alienation. The unrest has forced France to confront its failure to integrate minorities and the anger simmering among its large African and Arab communities.

No trouble anywhere in Paris was reported overnight into today. injured after being hit with a metal ball dropped from an apartment building, said national police spokesman Laurent Carron, who also detailed the troubles in Carpentras.

Rioting has weakened in intensity since the government declared a state of emergency Tuesday, empowering regions to impose curfews and conduct house searches.

Some 40 towns, suburbs and small cities have imposed curfews on minors.

Ban on gatherings

Paris police banned public gatherings that could “provoke or encourage disorder” from 10 a.m. Saturday to 8 a.m. today. It was the first such ban in the French capital in at least a decade, said police spokesman Hugo Mahboubi.

Police counted 315 cars torched and said 161 people were arrested across France overnight before dawn today.

Calls for peace and political change mounted.

Several hundred people demonstrated against the state of emergency in Paris’ Latin Quarter, a gathering that police allowed because it was not deemed risky. Under tight police surveillance, the protesters called the new security measures a “provocation” that would not resolve the social and economic problems underlying the unrest.

The protesters, many from left-wing political groups and Communist-backed unions, called for the resignation of Interior Minister Nicolas Sarkozy, who has been accused of inflaming the violence by calling troublemakers “scum.”

A similar rally in the southern city of Toulouse drew about 700 people.

In Blangnac, on the outskirts of Toulouse, arsonists set fire to an electronics store on Saturday night, the regional government said. No injuries were reported.

Late Friday, two gasoline bombs slightly damaged a mosque in Carpentras, a city grimly remembered for a 1990 neo-Nazi attack on a Jewish cemetery that sparked national outrage.

President Jacques Chirac called on investigators to find the perpetrators.

Some 2,503 people have been detained since the trouble started, with 364 of them convicted in expedited trials. Nearly 460 minors have gone before juvenile courts, 103 of whom were in the process of being charged, the Justice Ministry said.