The French government has declared states of emergency in more than 30 cities and towns, giving local authorities the power to impose curfews to stop another night of riots.

Police say the number of violent incidents has dropped since the emergency decrees took effect. Only a few incidents have been reported since nightfall Wednesday. Muslim youths of North African descent have mainly been responsible for the two weeks of riots.

The government has promised to address what many French say are the causes of the violence -- unemployment, poor schools and housing, and racism. French Interior Minister Nicolas Sarkozy Wednesday said foreigners who incite violence would be deported.