Unidentified woman is said to have a history of psychiatric issues, and has been left in critical condition.
Paris police shot and seriously injured a woman who made threatening remarks and shouted "Allah Akbar" on a train on Tuesday.
The police were called in after two passengers reported at around 07:30 that a woman wearing a "full veil" was making threats on a train in Val-de-Marne, Paris police prefect Laurent Nuñez told a press conference.
The incident comes as France grapples with rising tensions over the war between Israel and Hamas.
Prefect Nuñez added that according to witnesses, the woman also shouted: "You're all going to die".
According to the police commissioner, she was subsequently located by police at the Bibliothèque François Mitterrand station in Paris, which was quickly evacuated.
The police officers "asked her to sit down on the ground", explained the prefect, but the woman got up and "went towards the police officers". They asked her not to move and to show her hands to check that she had no weapon, but she "refused to comply".
Two police officers then fired eight shots, said the public prosecutor, who had initially reported a single shot was fired by a police officer.
The woman was seriously injured in the abdomen and hospitalised. Police say her injuries are life-threatening.
Checks established that she had neither explosives nor a weapon on her person. The station was still closed early on Tuesday afternoon, and Transport Minister Clément Beaune visited the scene.
The woman, aged 38, had already been stopped in July 2021 by soldiers during Operation Sentinelle. That day, "also wearing a full veil" and carrying a "screwdriver", she had made "religious remarks" with a "threatening attitude", explained Laurent Nuñez.
She was held in police custody for a time before being "interned" because she was suffering from "psychiatric problems".
She had not been the subject of a radicalisation file, contrary to what police sources had initially indicated.
The identity of the woman, who gave her name to the hospital but had no identity papers with her, has yet to be confirmed, officials stressed.
Two investigations have been opened. One has been entrusted to the Paris judicial police for "apology, death threats and intimidation of a public official"; the other has been entrusted to the General Inspectorate of the National Police (IGPN) and concerns the police officers' decision to shoot, as happenes whenever a police officer uses a firearm.
This case comes at a time of tension in France, due to the war in Gaza between Israel and Hamas, and following the murder of teacher Dominique Bernard in Arras on 13 October by a young man with a record of Islamic radicalism.
Since the attack, France has moved its national terror alert to the highest level of readiness. Bomb threats have been issued at dozens of locations in France, leading to multiple evacuations of airports, train stations and tourist sites such as the Palace of Versailles.
A total of 100 bomb threats have been made to French airports since 18 October, the French Minister for Transport, Clément Beaune, said on Tuesday.
On Monday, Interior Minister Gérald Darmanin recorded "819 anti-Semitic acts" and "414 arrests" in France since October 7th, when Hamas fighters stormed into Israel and murdered hundreds of people before abducting hundreds of hostages. Israel has responded with its largest assault on Gaza since it withdrew from the area in the mid-2000s.