A gunman is holding several people hostage in a supermarket in Trèbes, in the south of France.
French media say the man had earlier fired shots at some policemen who were jogging, wounding one of them, but not critically.
Elite police have rushed to the Super U shop in Trèbes, near Carcassonne.
A prosecutor says the gunman claims to be in the Islamic State group. In January 2015 a jihadist gunman killed four people in a Paris supermarket.
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Prime Minister Édouard Philippe said the situation was “serious”. Local media are reporting that one person has been killed but authorities are yet to confirm this.
Hundreds of police officers have been deployed to the scene and the area has been cordoned off.