( AFP ) - French police tightened security Tuesday as 64 officers were injured following a second night of massive rioting in flashpoint Paris suburbs over the deaths of two teenagers.
A helicopter hovered early Tuesday over the town of Villiers-le-Bel, 20 kilometres ( 12 miles) north of the French capital "to locate people stirring up trouble," a police officer told AFP.
The violence broke out in the suburb Sunday after two teenagers died when their motorcycle collided with a police car, and rapidly spread to nearby areas.
A police source Tuesday said 64 officers were injured on Monday night in fresh clashes with angry youths in Villiers-le-Bel and two nearby towns, and added that five of them were in critical condition.
"One policeman was wounded in the shoulder after being hit by a high-calibre bullet," a security official said, adding that "however, no vital organ was affected."
Late Monday, some 100 angry youths crouching behind trash cans in Villiers-le-Bel hurled objects at 160 riot police who responded with rubber bullets and teargas.
Young rioters in other towns were armed with Molotov cocktail bombs, bottles filled with acid and baseball bats, police said.
They said 63 vehicles and five buildings had been torched.
After Sunday's first night of unrest, President Nicolas Sarkozy appealed for calm, with France fearful of a repeat of nationwide violence that gripped the country in 2005 following the deaths of two youths fleeing the police.
Speaking on a trip to Beijing, Sarkozy called for "all sides to calm down and for the judiciary to decide who bears responsibility".
On Monday, a bus, which had no passengers on board at the time, and a lorry were set alight respectively in nearby Longjumeau and Grigby, police sources said.
In Villiers-le-Bel, a pre-school, a driving school and a beauty salon were also set ablaze, witnesses said. Youths stoned a police car and a fire engine as well as looting another vehicle.
State prosecutor Marie-Therese Givry ordered an internal police investigation for "involuntary manslaughter and failure to assist persons in danger" following the deaths of the two teenagers.
Speaking later to reporters, she said witnesses had confirmed the police officers' version that the bike smashed into the side of their car during a routine patrol. Neither youth was wearing a helmet.
But Omar Sehhouli, brother of one of the victims, accused police of ramming the motorbike and of running away.
"This is a failure to assist a person in danger... it is 100-percent a (police) blunder. They know it, and that's why they did not stay at the scene," he told France Info radio.
Sehhouli told AFP the rioting "was not violence but an expression of rage."
Police made nine arrests Sunday as rioters torched a police station, two garages, a petrol pump and two shops, and pillaged the railway station in neighbouring Arnouville. Some 40 police were reported injured.
The police union Alliance offered its condolences to the victims' families, but said it was "unacceptable for a gang of delinquents to use this tragedy as an excuse to set the town on fire."
Police and politicians warn the French suburbs remain a "tinderbox" two years after the 2005 riots, which exposed France's failure to integrate its large black and Arab population, the children and grandchildren of immigrants from its African colonies.