AIX-EN-PROVENCE, France - Six teenagers went on trial in southern France on Monday over the torching of a bus in 2006, which left one young woman severely burned.

The trial spotlights the problem of urban violence in France again, just a week after youths in a suburb north of Paris clashed with police and set fire to shops, cars and public buildings in two consecutive nights of unrest.

The six youths facing trial are suspected of being part of a gang of eight who attacked a bus in the southern port city of Marseille last October, spraying petrol on the seats and setting it ablaze as passengers tried to flee.

One passenger, Mama Galledou, a student from Senegal, caught fire and spent months in hospital recovering from severe burns covering 62 percent of her body.

The six teenagers, aged between 16 and 18 years, are accused of arson inflicting a handicap or mutilation and face up to 30 years in prison. Two younger boys were sentenced to eight years in prison by a juvenile court in September.

The Marseille incident followed a number of similar attacks on buses near Paris around the anniversary of 2005 riots in France's run-down suburbs, where many descendants of immigrants from Africa live.

Many youths in the bleak and often isolated housing estates surrounding France's big cities say they are discriminated against when trying to find a job or housing and say they feel like second-class citizens.

Media have quoted the arrested youths as saying they wanted the same attention as was given to the violence happening near Paris at the time.

Some of the youths' lawyers said they feared last week's violence near Paris could weigh on the trial.

"I don't want the decision in Marseille to be a precedent," lawyer Thierry Ospital said.

President Nicolas Sarkozy, interior minister at the time of the 2005 riots, has taken a tough stance on last week's urban violence and promised to arrest all rioters.

To Galledou, the injured woman, the severity of the youths' sentence, if they are found guilty, is of little importance, her lawyer said.

"(If found guilty), whether these attackers get several months or many years in prison is of little interest. It won't give her her health back," lawyer Alain Molla said. "She expects the truth from this trial, more than obvious excuses."

The verdict at the court for minors in the southern city of Aix-en-Provence, which is closed to the public, is due on Friday.