Terrorists who left 13 people dead and more than 100 injured when a van driver struck pedestrians on Aug. 17, 2017, also planned another attack during Barcelona's first La Liga game three days later.
Five of the men responsible were killed by police two days before the game, which went on as planned with players wearing black armbands and the name of the city on their shirts in place of their names.
Members of the cell also reportedly visited the Camp Nou team store, leading investigators to conclude they planned to enter the stadium dressed as fans.
The Barcelona source also said the club had redoubled their efforts to improve the security at the Camp Nou and the rest of their facilities since the attack, and are not aware of any terrorist alert in the past year.
Via ESPN