Three women arrested in France had planned to attack Paris railway station

French officials arrested three women Thursday night who had been plotting an attack on a major transit hub in Paris.

One of the security officials, who was not authorized to be publicly identified, said French authorities found a note on Madani declaring allegiance to the extremist group, which has called on followers to attack France. “They were guided by individuals in Syria in the ranks of Islamic State”.

Four people – two brothers and their girlfriends – are already in custody over the discovery of the auto.

Police and officers from the DGSI, France’s counter terrorism intelligence agency, had been on the trail of the trio since Sunday, when a auto full of gas canisters was found parked in Paris.

“Others are out there”, French President Francois Hollande said on the sidelines of a summit of southern European states in Athens yesterday.

Molins said the woman was engaged to Larossi Abballa, who killed two police officials in Magnanville in June and filmed the aftermath on Facebook Live before dying in a police raid.

The youngest of those held, aged 19, is said to have written a letter pledging allegiance to Islamic State.

France’s interior minister described the pursuit as “a race against time” to find Madani and the two women with her before they struck.

Security around Paris was visibly higher Friday as the investigation widened.

Investigators are trying to establish whether any of those arrested and questioned have links with Hayat Boumeddiene, the girlfriend of Amedy Coulibaly, who killed a police officer and four hostages at a kosher supermarket in Paris in January 2015.

One of the women, Ines, aged 19 was reportedly shot in the ankle and thigh after she hurled at one security officer with a knife upon seeing the police vehicle in front of the building.

Two brothers and their girlfriends have also been arrested on Wednesday and Thursday.

Ines Madani also knew Rachid Kassim, one of the extremists suspected of being connected to the murder of Father Jacques Hamel in northern Saint-Etienne-du-Rouvray in July, RTBF said.

French Interior Minister Bernard Cazeneuve told the press on Thursday that the suspects were aged 39, 23 and 19, were “radicalized fanatics” and “likely preparing violent actions”.

Police sources said no detonator had been found.

France has been under a state of emergency since the Paris terror attacks in November previous year, and authorities have struggled to monitor thousands of domestic radicals on their radar.

The foiled plot comes two months after a Tunisian radical slammed a lorry into a crowd of Bastille Day revellers in Nice, killing 86 people.

“If at first it seemed that women were confined to carrying out family and domestic tasks by the terrorist organisation, we are now forced to see that vision is largely outdated”, he said.