The decryption of messages from the Islamist website Shoumouk al-Islam earlier this week has revealed that the Louvre and the Eiffel Tower might have narrowly escaped terrorist attacks, Le Parisien reports.

Ali M., a young Algerian man in communication with a senior member of AQMI (Al-Qaeda in the Islamic Maghreb), suggested the historical monuments as well as the Festival d’Avignon, bars, markets, clubs, and airplanes as potential targets for the group.

Satisfied by the response, the AQMI official invited Ali M. to join his troops in Algeria for a 10-day military training, before returning to France to “await his instructions.” But the new recruit was arrested before he could take off.

Ali M., a 29 year-old Algerian residing in southern France in the Vaucluse region, worked in a Halal butcher shop and is a father of two. The messages were discovered upon his arrest a year ago. They took a full year to decipher.

Judge Marc Trévidic has warned that the case of Ali M. is not an isolated one. The constant exodus of young French people to countries such as Syria, Mali, Afghanistan and Yemen—and the heightened risk of terrorist acts linked to their return—is a cause of great concern for the French government.

To better answer these threats, home office minister Bernard Cazeneuve has proposed a series of new security measures including the reinforcement of internet surveillance. Most of Al-Qaeda’s novices are now recruited online, one of the investigators told Le Parisien. “Their messages go viral on social media,” he added. “It’s going to be a difficult task.”