He reportedly was tasked by the mastermind behind the Paris attacks, Abdelhamid Abaaoud, to gather information about the Balkan route used by migrants and refugees so that Daesh terrorists could reach Paris to carry out the attacks.
The Algerian suspect apparently made a three-month journey from Syria to Western Europe, passing Turkey, Greece, Macedonia, Serbia, Hungary and Austria, and informed Abaaoud about opened border crossings and wait times.
He also was allegedly in direct contact with Moroccan jihadist Ayoub El Khazzani who opened fire on an Amsterdam-Paris train last August.
Before that, Bilal C. allegedly traveled to Syria where he joined Daesh and received training in a jihadist camp.
On November 13, Islamic terrorists conducted a series of coordinated attacks in the French capital, killing 130 people and injuring over 360, many critically. Daesh, outlawed in Russia and many other countries, claimed responsibility for the attack.