Multiple terrorist attacks were prevented this week in France, President Francois Hollande said Wednesday.
"Several terrorist attacks were thwarted this week," Hollande said on French national television station BFMTV 24 news.
The president's remarks came a day after two explosions rocked a petrochemical site near Berre-l'Etang by Aix-en-Province.
French Interior Minister Bernard Cazeneuve said earlier Wednesday that the explosions were "criminal acts, but the motivation has not yet been established."
Cazeneuve said that on "Monday, July 13, at dawn, four individuals between the age of 16 to 23, (including one who was) one a former military in the national navy" were arrested in four different parts of the country.
Cazeneuve said those arrested were planning to commit a terrorist act against French military installations. He said no link has been found at this point between those arrested and the explosions at the petrochemical site in Bouches-du-Rhône, the department in which Berre-l'Etang is located.
The prosecutor of Aix-en-Provence, Dominuqe Moyal, confirmed on BFMTV Wednesday that an official investigation was underway and said "material had been found near the explosions," which affected two storage tanks. Similar material was found at a third tank, he said.
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Le Figaro newspaper reported that investigators found a passage had been made through a fence near one of the tanks that was set on fire.
The Ministry of Interior has asked for security reinforcements at all sensitive industrial sites.
Those responsible will be "hunted, found and condemned," Hollande said.
The "main instigator" of the four arrested Monday came to the attention of authorities for his activism related to "French jihadists" currently imprisoned, Cazeneuve said. The instigator, who has not been identified, also reportedly had plans to depart for Syria, Cazeneuve said.
"Every week, we stop, we stop, we prevent terrorist acts," Cazeneuve said Thursday.
