Last week, hours after the vehicle was found, counter terrorist police arrested Ines Madani, 19, Sarah Hervouet, 23, and 39-year-old Amel Sakaou at an apartment in a Paris suburb.
During the arrest Hervouet stabbed a policeman, injuring him in the shoulder, while Madani was shot in the leg after she charged at an officer with a knife.
A fourth woman, 29-year-old Ornella Gilligman, was charged at the weekend after confessing she and Madani tried to set the car on fire before fleeing after they saw a man they thought was a police officer approach the vehicle.
The car was later found to contain five gas cylinders and three bottles of diesel.
Both women were known to police for their links to Islamist radicals and officers believe they were also contemplating obtaining suicide belts or ramming cars filled with explosives into buildings.
One of the women is alleged to have been found in possession of a letter professing her allegiance to Islamic State.
The suspects were charged as France remains on its highest state of alert following two attacks in July where a truck was driven into spectators in Nice on Bastille Day, killing 86 people and two men slit the throat of priest Jacques Hamel in Normandy.
The country was increasingly targeted by Islamist extremists last year, with 12 people killed during an attack on satirical magazine Charlie Hebdo in January and 130 people killed by marauding gunmen in Paris nine months later.
Police are becoming increasingly concerned about the influence 29-year-old Frenchman Rachid Kassim may be having on Islamist extremists in France via social media.
The former youth leader left the country for Egypt in 2012 and recently featured in a graphic IS video in which he appears to kill two Syrian men before threatening France with attacks by French citizens.
He is alleged to have exchanged messages with the murderers of priest Jacques Hamel and it has been revealed that Hervouet had been in a relationship with one of Hamel’s killers.
A 15-year-old boy arrested in eastern Paris at the weekend was also brought before investigating magistrates on Monday to be charged with conspiring to commit attacks.
The youth had written to contacts on Telegram, an encrypted messaging app widely used by jihadists, of his plans to carry out a knife attack, sources said.
On Sunday, Prime Minister Manuel Valls said 15,000 people in France are considered by authorities to be extremists who pose a potential threat.
News Source SkyNews