French authorities have said that three women arrested for planning an attack in Paris were being directed by the Islamic State of Iraq and the Levant.

Anti-terrorism prosecutor Francois Molins said on Friday that the three suspects were determined to carry out ISIL's "deadly ideology", and had been given direction by members of the Islamic State of Iraq and the Levant (ISIL) group members in Syria.

The women, aged 39, 23 and 19, were arrested on Thursday night as part of a probe into a car, loaded with six gas cylinders and three cans of diesel, that was found on Sunday parked near Notre Dame Cathedral.

During the arrest one of the women, identified as Sarah H, 23, stabbed a policeman in the shoulder who had been keeping watch on them from an unmarked car near the apartment, the investigator said.

Teams of police then swooped on the women and in the struggle, the 19-year-old Ines Madani was shot in the thigh and the ankle.

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According to Interior Minister Bernard Cazeneuve, the women were preparing "new violent ... and imminent actions".

Four other suspects linked to the alleged attack plot - including two brothers and their girlfriends who are aged between 26 and 34 - were arrested separately on Tuesday on Wednesday.

Plots foiled

A bar employee working near Notre Dame had first raised the alert on Sunday after noticing a gas cylinder on the back seat of the parked car, police said.

The car had no number plates and its hazard lights were flashing.

Although the cylinder on the back seat was empty, five full cylinders were discovered in the boot. Three bottles of diesel fuel were also discovered in the vehicle, but police found no detonators.

"If it was an attack plot, the method was very strange," a police source said on Thursday.

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France is on high alert following a string of attacks claimed by ISIL, including last November's coordinated attacks in which assailants killed 130 people in Paris.

Speaking on Thursday, President Francois Hollande referred to attack plots that have been foiled "in recent days", without elaborating.

Cazeneuve on Friday told French daily La Presse that 260 people have been arrested in connection with terrorist networks or operations since the beginning of the year.