Paris - Weekend violence outside Paris triggered by France's controversial veil ban has highlighted how tensions with the Muslim community are adding to an already-volatile mix of poverty and alienation in the country's blighted suburbs.
The unrest in the Paris suburb of Trappes erupted after a man was arrested for allegedly attacking a police officer who stopped his wife over wearing a full-face veil in public.
Feelings of anti-Muslim discrimination, coupled with unemployment and tensions with police are creating an "explosive" mix in the suburbs, said Veronique Le Goaziou, a sociologist and expert on urban violence in France.
"These areas are pressure-cookers," she said.
The violence kicked off on Friday evening, when about 400 people protested near the Trappes police station, southwest of Paris.
They set fire to bins, destroyed bus stops and hurled stones at police who responded with tear gas. A 14-year-old boy suffered a serious eye injury and several police officers were also hurt.
Trigger for unrest
The disturbances continued on Saturday night, albeit to a lesser degree, and by Sunday a tense calm had been restored.
Police actions are often the trigger for unrest in France's working-class suburbs, including in 2005 when weeks of rioting broke out after the deaths of two teenage boys in the Paris suburb of Clichy-sous-Bois.
The two were electrocuted when they climbed into an electricity substation as they tried to escape police chasing them.
Riots last year in the northern city of Amiens were set off by police identity checks.
Critics have described frequent identity checks in immigrant neighbourhoods as "police harassment", and studies have shown that people of African and Arab descent can face up to 10 times more spot ID checks than white people.
"Every time there is urban violence, it's linked to a police operation. This shows to what extent relations between residents of working-class neighbourhoods and police forces are problematic," Le Goaziou said.
'Tensions moving into field of Islam'
A few kilometres from the Chateau de Versailles, Trappes is a poor city of 30 000 surrounded by wealthy neighbours. In 2010, half the households lived on less than €13 400 a year and unemployment was at 15%.
"This is a terrifyingly common situation," said sociologist Michel Kokoreff. "We are in an area that has problem after problem, where people have a profound feeling of abandonment."
That the latest unrest was set off in part by the ban on full-face veils underscores the increasingly tense ties between authorities and the Muslim community, observers say.
"Tensions are moving into the field of Islam," Kokoreff said.
The veil ban, introduced in 2011, has outraged many in France's Muslim community, which at an estimated four million is western Europe's largest Muslim minority.
Officials say more than 700 women have been stopped since the ban was introduced.
Radical Islamic groups
The growing visibility of French Muslims has also sparked a backlash from nationalists and been a key factor in the increasing popularity of the far-right National Front.
"For several years there has been a rise in the feeling of persecution among non-Muslims, who have the impression that Islam is imposing its views, and on the other side, among Muslims who have the impression they are always stigmatised," said religious anthropologist Dounia Bouzar.
And in some areas, including Trappes with its large Muslim population, radical Islamic groups have emerged and are fuelling tensions, she said.
"These new religious movements are feeding on inequality and frustration," she said. "When people feel like they have no place in society, [radical] Salafist discourse turns the situation around by giving them a feeling of power."