French police have arrested a 15-year-old boy suspected of planning an “imminent” terror attack.

The teenager was arrested in eastern Paris on Saturday and had been under house arrest since April for suspected links to Isis.

His arrest came as he was planning an attack in a public place in the French capital, a source told AFP.

Police suspect him of plotting "in response to calls from Syria to attack France", the source added.A second source said the boy had been in contact with suspected French militant Rashid Kassim over the encrypted messaging system Telegram.  

Last Sunday, a car loaded with gas cylinders was found near Notre Dame cathedral, leading to the discovery of a plot to attack a Paris railway station under direction of the so-called Islamic State.

Following the incident, seven people, including four women, were arrested.

One of the women arrested was also thought to have been guided by Kassim.

French newspaper Le Monde quoted a message from Kassim on Telegram saying: “Women, sisters, go on, attack. Where are the brothers?...She brandished a knife and she hit a policeman...Where are the men?", referring to the arrest of a group of women on Thursday in relation to the railway station plot.

The women were arrested after police linked the car at the scene to a house in the Essonne region south of Paris.

During the arrest, the 19-year-old daughter of the car's owner, Ines Madani was shot in the leg when she lunged at a police officer with a knife.

Another woman, Sarah H, 23, attacked and wounded a plain clothes officer with a kitchen knife through the open window of his car.

A third woman, Amel S, 39, who lived at the house, also was arrested along with her daughter, who was about to turn 16 and was potentially implicated in the "terrorist project," according to the prosecutor.

Another woman, Ornella G, arrested on Tuesday, was charged by a French judge on Saturday in connection with the car found near Notre Dame cathedral.

Authorities suspect the woman is part of a female "terrorist commando" in the service of Isis.

Kassim, 29, who is thought to be in Syria, is also believed to have inspired the two men who executed an elderly priest in a Normandy church in July.

The attack shocked France, coming less than two weeks after another Isis militant drove a truck into crowds celebrating Bastille Day in Nice.

On Sunday, Prime Minister Manuel Valls said that around 15,000 people were known to police in France as having been radicalised, up from a previous estimate of 10,000.

He said around 700 jihadists from France were fighting in Syria and Iraq.

(Independent)