Remy Heitz said in a statement the 24-year-old man has admitted making the bomb and depositing the device in front of a bakery. He will be brought before an investigating judge. The suspect, identified only as Mohamed Hichem M., was arrested on Monday. He arrived in France on a tourist visa in August 2017 but failed to leave again. Police did not give his nationality but some French media reported that he was Algerian. He was unknown to police services before the incident.
He was handed preliminary charges Friday of attempted murder, criminal terrorist conspiracy and manufacturing, possessing and carrying an explosive device in relation with a terrorist undertaking. French President Emmanuel Macron had called the explosion an "attack" but no group has claimed responsibility for the explosion yet.
Last week, Heitz described video surveillance that showed a man heading toward the center of Lyon on a bike. He was seen arriving on foot, pushing his bike along a pedestrian-only street, then leaving a paper bag on a concrete block in the middle of the street. The suspect immediately returned to his bike and left the same way. One minute later, the explosion shattered the glass of a refrigerator in the bakery.
The suspect initially denied his involvement, then admitted "pledging allegiance to the IS deep down inside and dropping off the explosive device he had prepared beforehand," Heitz said. Data analysis of a computer used by the suspect until the end of last year also helped investigators establish he had an interest for "jihadi thesis and IS's activities."
The police probe also established that the suspect had ordered online a pack of 20 batteries corresponding to those that served to remotely trigger the device. Some traces found on evidence discovered at the scene also matched the suspect's genetic profile, Heitz said.
The suspect was arrested along with his parents and brother, but they were released on Thursday without charges. France has been hit by a spate of attacks in recent years, some of them deadly, carried out by people ranging from extremist attackers to mentally unstable individuals.