France's government has issued a decree declaring a state of emergency in Paris and more than 30 other towns and cities following a 13th night of rioting.
Only Amiens, in the north, has so far imposed an overnight curfew under the new powers - in force since midnight.
Police said overnight violence was down, but Lyon's public transport network was shut by a petrol bombing.
Interior Minister Nicolas Sarkozy has issued an order to deport foreigners convicted of involvement.
Mr Sarkozy told parliament that 120 foreigners - "not all of whom are here illegally" - had been convicted of taking part in the nightly attacks.
"I have asked the prefects to deport them from our national territory without delay, including those who have a residency visa," he said.
The areas covered by the special decree, giving local authorities and police emergency powers to deal with rioters, were listed on Wednesday.
KEY TOWNS UNDER EMERGENCY DECREE
They extend from the English Channel to the Mediterranean, including Paris suburbs and major cities such as Lille, Marseille and Toulouse, where police clashed with groups of youths overnight.
Two Paris suburbs, Savigny-sur-Orge and Le Raincy, as well as the historic city of Orleans, have already declared separate curfews not covered by the law.
On Wednesday, police reported a drop in the level of violence across France as a whole, with the number of cars set alight falling to 617, hundreds fewer than the night before.
Some 280 people were arrested and disturbances broke out in 116 areas, half the number affected the preceding night.
Despite this, incidents were reported in several areas:
- A gas-powered bus exploded in the suburbs of the south-western city of Bordeaux after it was hit by a petrol bomb
- Youths in the city of Toulouse, also in the south-west, threw petrol bombs at police and set fire to cars
- The offices of the Nice-Matin newspaper, in the south-eastern town of Grasse, were set alight.
Paris, where the rioting began nearly two weeks ago, was relatively calm with some isolated cases of arson and a dozen arrests, police said.
Shortly before the decree came into effect, Mr Sarkozy, on a visit to Toulouse, said police were reporting a "fairly significant fall" in violence.
Cabinet can declare state of emergency in all or part of the country
Regional leaders given exceptional powers to apply curfew
Breach of curfew could mean two-month jail sentence
Police can carry out raids on suspected weapons stockpiles
Interior minister can issue house-arrest warrants for those deemed dangerous to public safety
Public meeting places can be closed down
House searches possible day or night
Authorities can control media, film and theatre performances
Emergency can only be extended beyond 12 days if approved by parliament
The powers, which can be extended by parliament after 12 days, allow a state of emergency to be declared in defined areas, restricting the movement of people and vehicles.
Police are entitled to carry out house searches and ban public meetings.
Minors are subject to the law between 2200 and 0600 (2100 and 0500 GMT) unless accompanied by an adult, and are also banned from buying petrol.
Nearly three out of four French people support the powers, according to a poll of 805 people published in the daily Le Parisien newspaper.
But some opposition parties, and the French magistrates association, have described them as a danger to civil liberties.
The far-right French politician Jean-Marie Le Pen told the BBC that rioters should have their French citizenship revoked.
The nightly protests have gripped deprived areas where unemployment is rife and residents complain of racism and discrimination.
The unrest was first sparked by the deaths in the run-down Paris suburb of Clichy-sous-Bois of two youths, who were accidentally electrocuted at an electricity sub-station.
Locals said they were being chased by the police, but the police deny this.
The new emergency powers handed to local authorities have been invoked under a 1955 law.
It was originally passed to combat violence in Algeria during the war of independence from 1954 to 1962. It was also used in New Caledonia in 1985.
This is the first time the law has been implemented in mainland France.