France ? Marauding youths torched hundreds of vehicles overnight and on Saturday in renewed violence coinciding with the first anniversary of riots that exposed a deep schism between poor North African immigrants and mainstream France.

A group of teenagers set one bus on fire Saturday in the southern French port city of Marseille, seriously wounding a passenger. Three others suffered from smoke inhalation, police said. Two other public buses and 277 vehicles around the country were burned overnight, police said.

Six police were injured and 47 people were arrested, ministry officials said. Still, the Interior Ministry described the night as “relative calm,” noting that up to 100 cars are torched by youths in troubled neighborhoods on an average night.

Police had braced for a bigger replay of violence in the poor suburbs predominantly made up of Muslims from former French colonies in Africa. Friday marked the one-year anniversary of the deaths of two teens that ignited three weeks of riots in 2005.