Riots hit a French city centre for the first time during this unrest on Saturday when police fought youths in Lyon.
Interior Minister Nicolas Sarkozy was out encouraging Parisian police officers as they clamped down on gatherings.
Mr Sarkozy's use of the word "racaille" (rabble) for hooligans has been taken up by civil rights protesters.
Riot police were preparing for another night of tension in the southern city of Toulouse.
The city had seen a march by about 1,000 people against discrimination earlier on Saturday.
Toulouse suburbs are littered with debris from the riots like this charred car.
Muslims in the southern French town of Carpentras woke to find a mosque charred by petrol bombs.