Cazeneuve said in an interview to the broadcaster that the police detained seven people overnight, suspecting their involvement in the terror attack, without revealing other details.
French Prime Minister Manuel Valls said that authorities have managed to intercept the activities of several groups linked with plotting terror attacks.
"Hundreds of people are being currently monitored and dozens have been detained," he said in a interview to RTL.
Earlier in the day, it was reported that police identified three suspects of the attacks. One of them, 18-year-old Hamyd Mourad, has since turned himself in to the police, saying that he has an alibi. The two other suspects identified are brothers Said and Cherif Kouach – French nationals of Algerian origin in their 30s.
On Wednesday morning, three gunmen attacked the office of satirical weekly magazine Charlie Hebdo, killing 12 people, including four cartoonists, two police officers and a commentator for the France Inter radio network. Another 11 people were injured.
