Then he sent for the Mexican ambassadors, and acquainted them with his discovery of the plot, saying that it grieved him much to find Montezuma mixed up in so treacherous an affair, and that the Spaniards must now march as enemies against a monarch they had hoped to visit as a friend. The ambassadors, however, asserted their entire ignorance of the conspiracy, and their belief that Montezuma also knew nothing of it. The night that followed was one of intense anxiety; every soldier lay down fully armed, and the number of sentinels was doubled; but all remained quiet in the populous city, and the only sounds which reached their ears were the hoarse cries of the priests who, from the turrets of the teocallis, proclaimed through their trumpets the watches of the night. With the first streak of morning light Cortes was on horseback, directing the movements of his little band, part of which he posted in the great square court. A strong guard was placed at each of the three gates, and the rest had charge of the great guns which were outside the enclosure, and so placed as to command the roads which led to the teocalli. The arrangements were hardly completed before the Cholulan caciques appeared, bringing a larger body of porters than had been demanded. They were marched at once into the square, which was, as we have seen, completely lined by the Spanish troops. Cortes then took the caciques aside, and sternly and abruptly charged them with the conspiracy, taking care to show that he knew every detail. The Cholulans were thunderstruck, and gazed with awe upon the strangers who seemed to have the power of reading their most secret thoughts. They made no attempt to deny the accusation, but tried to excuse themselves by throwing the blame on Montezuma. Cortes, however, declared with still more indignation that such a pretence would not serve them, and that he would now make such an example of them as should be a warning to the cities far and near, and then the fatal signal--the firing of a gun--was given, and in an instant every musket and crossbow was levelled at the unhappy Cholulans as they stood crowded together in the centre. They were completely taken by surprise, having heard nothing of what was going forward, and offered hardly any resistance to the Spanish soldiers, who followed up the discharge of their pieces by rushing upon them with their swords and mowing them down in ranks as they stood.