Armed police have rushed to the scene, located near Porte d’Arras metro station in the south of the city.
The shots are believed to have fired at Jacques Febvrier square, a few metres from the metro station, according to reports.
Witnesses reported at least three injuries, including a boy, thought to be aged 14.
The 14-year-old boy is believed to have been shot in the leg and another is said to have received neck injuries, say local media.
Two of the wounded were found at the scene, while the third made their way to a nearby hospital.
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