This file photo taken on August 15, 2016, shows French soldiers patroling in front of Notre Dame cathedral in Paris.聽French anti-terror police were holding two suspects on September 7, 2016, after finding several gas cylinders in a car near the聽cathedral, sources close to the investigation said. AFP
PARIS, France 鈥� French police were holding a couple with links to radical Islam on Wednesday after gas cylinders were found in a car near Paris鈥檚 Notre Dame cathedral, sources close to the investigation said.
The Peugeot 607 was discovered abandoned, with its headlights flashing, at the weekend in a part of the city that is hugely popular with tourists, the sources said.
Anti-terror investigators have launched a probe and the man and woman, both known to security services, were arrested Tuesday on a motorway in southern France.
The car鈥檚 owner, known to authorities for his Islamist preaching, was released on Tuesday evening.
His daughter, whom he described to investigators as radicalized, was being sought by police Wednesday, a police source said.
France remains on high alert after a string of jihadist attacks, including last November鈥檚 coordinated Islamic State (IS) group assaults in Paris by gunmen and suicide bombers who killed 130 people.
A bar employee working near Notre Dame raised the alert on Sunday after noticing a gas cylinder on the back seat of the car, which had no number plates, a police source said.
That cylinder was found to be empty but five full cylinders were found in the boot of the car.
No detonators were found, police said.
Photographs of the metallic silver-colored car after it was discovered showed its boot open and the gas canisters placed on the ground in a quiet side street opposite the cathedral.
鈥楶arked for two hours鈥�
Florence Berthout, the mayor of the district where the vehicle was found, complained in a letter to the Paris police chief that the car was 鈥渋llegally parked for over two hours, despite several telephone calls to police headquarters鈥�.
The criticism comes after authorities faced heavy fire for alleged security lapses in July, when 86 people were killed by an Algerian plowing a truck into a crowd celebrating Bastille Day in the resort of Nice.
The ISIS said the driver, Mohamed Lahouaiej Bouhlel, was one of its followers.
Less than two weeks later, two young jihadists murdered a priest near the northern city of Rouen.
Interior Minister Bernard Cazeneuve said the latest arrests came at a time of heightened vigilance for potential attacks, but added that 鈥渢he intentions of those arrested鈥� were as yet unknown.
Notre Dame, renowned for its flying buttresses, stained glass windows and gargoyles, is one of Paris鈥檚 most popular landmarks, attracting 13 million visitors each year.
The head of France鈥檚 DGSI domestic intelligence service, Patrick Calvar, warned in May of a 鈥渘ew form of attack鈥� in which explosive devices would be left near sites that attract large crowds.
Such attacks would create large numbers of victims without sacrificing suicide bombers, he told a parliamentary committee.
French security services are particularly worried about the danger posed by extremists returning from Syria after fighting with IS forces, with 700 French nationals still in the country, according to France鈥檚 top prosecutor.