The trial of suspects allegedly complicit in the planning of the 2018 Trèbes and Carcassonne terrorist attacks in the south of France opens on Monday in Paris. Three men were shot dead in a car park and a supermarket, and a receptionist was taken hostage until a gendarme, Arnaud Beltrame, volunteered to take the place of the captive at the cost of his life. FRANCE 24’s Claire Paccalin reports.