An armed teenager took four women hostage inside a newsagents in Toulouse, southwestern France, on Tuesday evening.
The unnamed 17-year-old suspect is known to police, having been arrested in December at a protest held by the yellow vest movement.
Police say the teenager eventually released the women without making any specific demands beforehand after an hours-long siege.
He fired at least one shot over the heads of police and asked for a negotiator, a police source told Reuters, adding that the incident did not appear to be terrorism-related.
The gunman has not yet surrendered to authorities.
A 300-metre security cordon has been erected around the store in the city's Blagnac suburb, and police have told neighbours to stay indoors.