On the march, Xi Zhongxun took out a map and said that they would bring a high-power radio and send messages as they went, giving the enemy the illusion that the main force of the troops had indeed arrived in Ansai. As expected, the Kuomintang discovered the Communist Army's high-power radio and made the same judgment as Xi Zhongxun imagined. Wei Hai even rushed over with his men. On the other hand, Ansai was full of mountains, forests and gullies, and other Kuomintang army leaders notified the troops to stop advancing. Zhu De also received the latest enemy situation. The reorganized 31st Brigade of the Kuomintang Army did not enter the ambush circle. Everyone was speculating that this place was very close to Yan'an, and whether the news had leaked out, but there was no other way at the moment, so they could only continue to stay where they were.