Zwingli’s reforming efforts were in full swing in June of 1524 and the images which besotted the city’s churches were removed at the order of the Magistrates. As Philip Schaff notes
In the presence of a deputation from the authorities of Church and State, accompanied by architects, masons and carpenters, the churches of the city were purged of pictures, relics, crucifixes, altars, candles, and all ornaments, the frescoes effaced, and the walls whitewashed, so that nothing remained but the bare building to be filled by a worshiping congregation. The pictures were broken and burnt, some given to those who had a claim, a few preserved as antiquities. The bones of the saints were buried. Even the organs were removed, and the Latin singing of the choir abolished, but fortunately afterwards replaced by congregational singing of psalms and hymns in the vernacular (in Basle as early as 1526, in St. Gall 1527, in Zurich in 1598). “Within thirteen days,” says Bullinger, “all the churches of the city were cleared; costly works of painting and sculpture, especially a beautiful table in the Waterchurch, were destroyed. The superstitious lamented; but the true believers rejoiced in it as a great and joyous worship of God.”
Schaff also remarks
The same work of destruction took place in the village churches in a less orderly way. Nothing was left but the bare buildings, empty, cold and forbidding.
Though ‘cold and forbidding’ is a bit of an overstatement. Bullinger’s Reformationsgeschichte contains a couple of engravings – reproduced here for your viewing pleasure:
The ‘good’ people of Zurich weren’t too happy with Zwingli about it all and in the middle of the month of June, 1524, they organized a demonstration, marched to his house, surrounded it, tossed eggs and stones at it, and chanted ‘down with the great devil!’ The Magistrates sent soldiers to disperse the crowds and that was essentially the end of the ‘Drive Zwingli Out of Town’ movement.
Schaff observes concerning Zwingli’s attitude towards images
It should be remarked also that he was not opposed to images as such any more than to poetry and music, but only to their idolatrous use in churches. In his reply to Valentin Compar of Uri (1525), he says, “The controversy is not about images which do not offend the faith and the honor of God, but about idols to which divine honors are paid. Where there is no danger of idolatry, the images may remain; but idols should not be tolerated. All the papists tell us that images are the books for the unlearned. But where has God commanded us to learn from such books?” He thought that the absence of images in churches would tend to increase the hunger for the Word of God.
This is patently correct.