Police inspect a car near a building in Boussy-Saint-Antoine on September 8.Geoffroy Van Der Hasselt / AFP / Getty

Updated September 9 at 1:19 p.m.

NEWS BRIEF French authorities announced Friday the arrest of a 19-year-old woman believed to be planning an attack after pledging allegiance to the Islamic State, Agence France-Presse reports.

The woman, identified as Ines Madani, was arrested alongside a 23-year-old woman and a 39-year-old woman Thursday in Boussy-Saint-Antoine, a suburb south of Paris, in connection with a discovery by French police Sunday of a vehicle found containing seven gas cylinders near Paris’s Notre Dame Cathedral. Though no detonator was found, police feared the car, a Peugeot 607 left with its hazard lights flashing without license plates, would be used for an attack.

Investigators say Madani, believed to be the daughter of the vehicle’s owner, was the primary suspect behind the foiled attack. Reuters reports the Peugeot’s owner alerted police Sunday of both his daughter and the car’s disappearance, further adding the daughter had been known to police for expressing aspirations to travel to Syria. One source close to the investigation said authorities found a letter in the woman’s possession in which she pledged her allegiance to the Islamic State.

Prosecutors said Friday that one of the women, known only as Sarah H., was found to have been engaged to be married to two men linked to attacks carried out earlier this year. Larossi Abballa, 25, was killed in a police raid in Magnanville after he pledged his allegiance to ISIS and killed a policeman and his partner in June. The other, 19-year-old Abdel-Malik Nabil Petitjean, was identified as one of two attackers responsible for the killing of a French priest during a church service in Normandy in July.  

Bernard Cazaneuve, the French interior minister, announced Thursday after the arrest that Madani had been shot and wounded, and that one officer was hospitalized for a knife wound inflicted by one of the women.

“These young women, aged 39, 23, and 19,  had been radicalized, were fanatics, and were presumably preparing an imminent, violent attack,” Cazaneuve said.  

French President François Hollande commended the police, and called for even greater vigilance.

“One group was destroyed, but there are others,” Hollande said Friday from a news conference in Athens, the Greek capital.

France has been under a national state of emergency following several high-profile attacks in the country in less than two years, including an attack in Nice in July in which 84 people were killed. Since the beginning of 2016, French authorities say more than 260 people have been arrested for links to terrorist networks.

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