Several youths, including two teenagers, have died in a firefight at a Marseille apartment block, according to police sources. The French port city is a known battleground between drug gangs.
The attackers, armed with automatic weapons, killed two 15-year-olds and a 24-year-old early Sunday, according to French officials.
The investigators found some 20 cartridges at the scene.
Prime Minister Manuel Valls expressed his "indignation" over the incident. "Nothing will stop the determination of the state to fight organized crime," he said on Twitter.
The shooters fired at the youths gathered at the foot of the Lauriers estate, notorious for its drug trade.
The murdered 24-year old man was known to the police, a source in the French judiciary told Agence France-Presse. He was also the target of the shooting, according to the uncle of one of the victims.
State crackdown on drugs
The police discovered two burnt cars, allegedly used by the attackers to approach and flee the scene, some 20 kilometers (12 miles) north of Marseille.
Clashes between drug gangs are not uncommon in the southern French city. Since the beginning of the year, police have arrested 132 individuals and seized 1.5 tons of cannabis and 39 kilograms (86 pounds) of cocaine, according to officials. Authorities also claim to have broken up 10 drug networks.
In May, hundreds of police officers stormed Lauriers estate as a part of a massive anti-drug operation, arresting around 20 people.
dj/cmk (AFP, dpa)