A young French woman was in critical condition on Saturday after a bus was set alight by teenagers in the southern French port city of Marseille in the latest bout of suburban violence, police and rescue services said.
"A 26-year-old woman was seriously burned" and taken to hospital, the Marseille fire service said, adding that "three other people were slightly affected by smoke" and also hospitalized after the attack around 9pm.
The woman's life was in danger after she suffered burns to nearly 60 percent of her body, a spokesperson for the hospital said.
Three adolescents pried open the bus doors and spilled a flammable liquid before striking a match, police said.
Marseille prosecutor Jacques Beaume called the attack "a real ambush."
"The bus was doused with gasoline and then set on fire," he said.
"A passenger is between life and death ... her condition is very serious," he said.
Beaume called for more wit-nesses to come forward, as of the "dozen passengers only three, four or five have been identified."
The attack happened in an area on the outskirts of France's second-largest city, which firefighters said did "not have a particular record of discourteousness or violence."
It came as France marked the first anniversary of the country's most serious riots in decades which passed without major incidents, with six policemen suffering minor injuries and two buses torched overnight on Friday, as well as scattered skirmishes with youths.