How was the House of Wisdom destroyed? The Mongol invaders ransacked it and threw all of the books into the river Tigris The Mongol invaders ransacked it and threw all of the books into the river Tigris , The government did not take care of building repairs and it had to be torn down The government did not take care of building repairs and it had to be torn down , The people of the city were angry at the scientists so they looted it The people of the city were angry at the scientists so they looted it The caliph ordered it burned to the ground The caliph ordered it burned to the ground ,