Protests erupted after police shot dead a 17-year-old boy on Tuesday, feeding deep-seated concerns about police violence and systemic racism inside the country. More than 600 people have been arrested in France, following another night of protests. Overnight from Thursday to Friday was marked by looting, fires and damage to public property, sparked by the killing of a teenage boy by police earlier in the week. France"s President Emmanuel Macron is due to chair a crisis meeting Friday afternoon, with protests now in their third night. He has denounced the violence, which has swept through several cities, including Marseille, Bordeaux, Lyon, Grenoble, Annecy, Toulouse and Saint-Etienne, as "unjustifiable". The protests were sparked by the shooting of 17-year-old Nahel M at point-blank range by the police on Tuesday, after he tried to drive away from a traffic stop in Nanterre, a Paris suburb. The officer who opened fire is now under formal investigation for homicide, with prosecutors saying the use of the firearm was not legally justified. The mother of Nahel, whose son is reportedly of Algerian and Morrocan descent, said she didn"t blame the whole police force for his death - just the officer who pulled the trigger. "He saw the face of an Arab, of a little kid, he wanted to take his life," she said. The incident has fed longstanding complaints of police violence and systemic racism inside law enforcement agencies from rights groups and within the low-income, racially mixed suburbs around major cities in France. Authorities mobilised 40,000 police and riot officers, including the elite Raid squad, across France on Thursday, though this massive deployment was not enough to stem the violence. "Last night, our police, gendarmes and firefighters again courageously confronted rare violence. In line with my firm instructions, they made 667 arrests," Interior Minister Gerald Darmanin wrote on Twitter. Like in previous days, many clashes with police were reported, with 200 officers injured. No information was available about injuries among the rest of the population. Government appeals to de-escalate the violence on Wednesday did not quell the widespread anger. Shops and businesses were ransacked in Paris, according to police. In the Parisian suburb Drancy, rioters used a truck to force the entrance to a shopping centre which was partly looted and burned, said another police source. Public buildings were targetted by groups, with Molotov cocktails thrown at a police office in Pau, while a town hall in Lille was stoned. The Pablo Picasso estate in Nanterre, where Nahel was from, experienced a third night of sustained violence with burned cars, firework mortars and homemade grenades, noted an AFP journalist. Armoured police vehicles rammed through the charred remains of cars that had been flipped and set ablaze in the northwestern Paris suburb. A bank branch was also set on fire, with "vengeance for Nahel" scrawled on walls. Macron on Wednesday said the shooting was unforgivable. Nahel is the second person this year in France to have been killed in a police shooting during a traffic stop. Last year, a record 13 people died in this way. — Euronews