The militia soon advanced across the bridge and up the main street. When they were some sixty or seventy yards away from the raiders John Brown gave the order to fire. Some of the militia fell. Other volleys followed; and the attacking party was thrown into disorder. Finally they were driven back to the bridge, and took up a position there until reinforcements arrived. As they retreated John Brown ordered his men back to the arsenal. In the lull of the firing nearly all the unarmed people who were still in the town fled to the hills. It was now one o'clock in the afternoon, and the band of raiders could have escaped to Loudoun Heights. But their leader wanted to carry the guns and ammunition away with him, and to do this he needed the aid of the rest of his men. He sent a messenger to one of his followers named Kagi, who was stationed with several others on the bank of the Shenandoah, with orders for him to hold the place a short time longer. The messenger, however, was fired on and wounded before he could reach Kagi, and the latter's party was soon attacked by a force of militia, and driven into the river. A large flat rock stood up in the river, and four of the five raiders reached this. There three of them fell before the fire of bullets, and the fourth was taken a prisoner. In similar ways the number of John Brown's men was much reduced. The leader realized the danger of the situation, and decided that his best chance of escape lay in using the prisoners he had captured as hostages for his band's safe retreat. He moved his men, and the more important of the prisoners, to a small brick building called the engine-house. There he said to his captives, "Gentlemen, perhaps you wonder why I have selected you from the others. It is because I believe you to be the most influential; and I have only to say now that you will have to share precisely the same fate that your friends extend to my men." He ordered the doors and windows barricaded, and port-holes cut in the walls. The engine-house now became the raiders' citadel, and the militia and bands of farmers who were arriving at Harper's Ferry released the prisoners who were still in the arsenal, and concentrated all their fire on the band in the small brick house. As the sun set the town filled with troops, and it was evident that the men in the fort would have to surrender. They kept up their firing, however, from the port-holes, and were answered with a rain of bullets aimed at the doors and windows. Both sides lost a number of men. Two of John Brown's sons had been shot during the day. Finally the leader asked if one of his prisoners would volunteer to go out among the citizens and induce them to cease firing on the fort, as they were endangering the lives of their friends, the other captives. He promised that if they would stop firing his men would do the same. One of the prisoners agreed to try this, and the firing ceased for a time.