In the 8th and 9th centuries, the iconoclast movement caused serious political unrest throughout the Empire. The emperor Leo III issued a decree in 726 against images, and ordered the destruction of a statue of Christ over one of the doors of the Chalke, an act that was fiercely resisted by the citizens. Constantine V convoked a church council in 754, which condemned the worship of images, after which many treasures were broken, burned, or painted over with depictions of trees, birds or animals: One source refers to the church of the Holy Virgin at Blachernae as having been transformed into a "fruit store and aviary". Following the death of her son Leo IV in 780, the empress Irene restored the veneration of images through the agency of the Second Council of Nicaea in 787.