It was another night of relative quiet across France but police fear it may be the calm before a weekend storm. The number of incidents of street violence was similar to Wednesday night but still much lower than before. Once again the trouble was mainly in provincial cities.Almost 400 cars were burned around the country and 168 people arrested. Only five of the country’s 96 local authorities had opted to use their newly enacted curfew powers. But officials say they will not be complacent and are bracing for a possible flare-up over the weekend. The police chief of Paris said riotors may be planning disturbances in the capital. He said there had had been messages posted on the internet urging what he described as “violent action” in the city. It was in the impoverished suburbs of Paris that the unrest first erupted two weeks ago. Interior Minister Nicholas Sarkozy has again used strong language against those behind the violence, referring to them as “scum”. But in a TV interview he said France needed to break from the failed social policies of the past 40 years.