PARIS, May 7 — Violent protests against the election of Nicolas Sarkozy as president of France ended early today with hundreds of people arrested, hundreds of cars gutted and hundreds of windows smashed in several cities across in France.

Some people fear the reaction is just a taste of what is likely to come if Mr. Sarkozy makes good on his campaign promises to push through controversial economic legislation during his first 100 days in office.

Agence France-Presse, citing national police headquarters, reported that 730 cars had been set afire overnight, 35 in Paris, and that 592 people had been arrested, 79 in the capital. It said 78 police officers had been injured.

Some of the most concentrated violence took place at Place de la Bastille in Paris where the police fired volley after volley of teargas cluster grenades that looked like fireworks before descending on the crowd of young protesters. At one point, the square — the site of the July 14, 1789, uprising that is celebrated annually — was thick with white teargas reflecting the orange glow of a car fire while silhouetted youths heaved paving stones at tight formations of armored riot police officers.