Four police officers were wounded when masked youths fired shotguns at them in a southern suburb of Paris on Sunday, the French interior minister has said.
Michele Alliot-Marie said about 30 people ambushed the officers after they were called to Grigny when a local bakery was vandalised.
Three officers were treated at the scene after being hit by lead shots. A fourth was admitted to hospital.
About 60 police were injured when riots broke out in other suburbs in November.
In 2005, the government declared a state of national emergency after three weeks of rioting erupted at housing estates in more than 30 towns and cities.
In a statement, Ms Alliot-Marie said police were called to an estate in Grigny on Sunday afternoon after several people vandalised a local bakery.
When the officers arrived, they were confronted by "about 30 people whose faces were masked and several of whom were armed," she added.
The armed youths fired cartridges containing lead shot and nails at the police, while others threw stones and Molotov cocktails, setting a car alight.
More than 30 French towns and cities were affected by 2005's rioting
Calm was restored an hour-and-a-half later after police reinforcements were sent to the neighbourhood and the youths dispersed.
Ms Alliot-Marie called for "all means to be used to identify, apprehend, and bring to justice the authors of these criminal acts" and for them to face "exemplary sentences".
Last month, President Nicolas Sarkozy announced a three-year proposal to deploy 4,000 more police and roll out a half-billion euro aid lifeline to the poor, mainly ethnic-minority suburbs across France wracked by riots in recent years.
He also unveiled plans to help 100,000 people find work and declared "war without mercy" on drug dealers, warning that unless such neighbourhoods were revived, the "very idea of the nation is at stake".