On the morning of October 17, a reconnaissance detachment of the ROK Army Intelligence Department led by a ROK Army Intelligence Division (Deputy Director) Colonel went to the front, and the ROK Army set up concealed observation points in several places to observe the battle situation and the situation on the 597.9 heights of the Volunteer Army using high-powered telescopes.

After half a day of careful observation, the people of the South Korean Army's intelligence department found that the volunteers were constantly fighting from several

The "underground exits" rushed out to reinforce and rescue the wounded to various positions, and each time the US military large-scale, high-intensity artillery bombardment and air raids were carried out before the volunteers changed from their original positions

"Underground exits" go underground and hidden; At the beginning of each large-scale artillery and air raid by the American army, there were almost no volunteers left on the positions.

In order to thoroughly implement the accuracy of the intelligence and report to the US military intelligence office, Colonel Yoon Jae-wook, deputy director of the ROK military intelligence department, decided to take a few people to the 597.9 high ground to inspect the site to finally determine the accuracy of the intelligence.

On the afternoon of 17 October, after the volunteers had all withdrawn into the tunnel after a bloody battle during the day, Yoon Jae-wook, deputy director of the ROK Army's intelligence department, led a few people to the surface position of the 597.9 Heights.

Yoon Jae-wook immediately returned to the US military intelligence chief, Colonel James, to report in detail the reconnaissance and verified information about the volunteer tunnels, and the US military finally thoroughly understood the reason why the volunteers were able to survive under super-saturated artillery fire and aviation fire; What are the two intelligence guys plotting again...... From the morning of October 17 to the evening of October 19, the nearly three-day battle was more fierce and brutal than the previous battle, and the Volunteers fought to the death with the US 7th Division and the South Korean 2nd Division in Shangganling; Due to the small area of Shangganling, the two sides were unable to deploy a large number of troops; Often, one company after another was put into battle, and some positions even changed hands several times a day.

On 18 and 19 October, the 7th Division of the US Army and the 2nd Division of South Korea even sent military police to supervise the battle, and on 18 October, after a day's fighting, for the first time, the surface positions of the 597.9 Heights and 537.7 Heights of the Volunteers were completely lost;

By the evening of October 19, the surface positions had once again fallen into the hands of the enemy, and 10 incomplete companies of the 45th Division had been gathered in the No. 1 tunnel; In order to unify the command of the troops in the tunnel, after democratic consultation, everyone once again combined the multiple companies in the No. 1 tunnel into a new reinforced company, and everyone unanimously elected Zhao Lianfa as the commander of the reinforced company and Li Wenwu as the instructor of the reinforced company; At the same time, five platoon commanders and several squad leaders were re-elected, and a temporary party branch was established, with Li Wenwu as the secretary of the party branch.

In the past three days of fighting, there was a change compared with the previous days, on the evening of October 17, several small shells fell at the mouth of the No. 1 tunnel (no casualties were caused by the tunnel troops of the Volunteer Army); On the evening of October 18, several nimble American soldiers threw several grenades at the entrance of Tunnel No. 2, and one soldier reacted quickly and threw one of them back, while Mao Shenhai, the instructor of the 6th Company of the 137th Regiment of Tunnel 2, killed an American soldier at the entrance of Tunnel 2 (the rest of the American troops are unknown); On the evening of the 19th, two U.S. Flamethrowers actually approached the mouth of the No. 1 pit under the cover of artillery fire and prepared to breathe fire.

Beginning on the evening of October 17, there were several instances of intelligence officers of the 2nd South Korean Division attempting to sabotage the tunnels of the volunteers on a small scale on the 537.7 heights in Buksan...... At around 5 p.m. on October 19, the company and platoon cadres, party members, and combat backbones of the reinforced company in the No. 1 tunnel of the 597.9 heights held another meeting to summarize the battle and make tactical arrangements for the rear (the meeting lasted about one hour).

The commander of the 6th Company of the former 137th Regiment of the Volunteer Army spoke first: "The attempts of the US Army and the Li Puppet Army to approach and destroy the tunnel from the 17th show that the enemy has confirmed the fact that our army is using the tunnel for defense and counterattack operations, and the enemy has begun to try to destroy our tunnel. For us, how to combat the enemy's sabotage behavior in the coming period is a problem that we face and must solve; At present, the enemy must be thinking about how to effectively destroy our tunnels, and I think that the enemy will first do everything possible to cut off and block the connection between our tunnels and the positions of the main peaks in our rear. ”

"Our army will soon have a counterattack tonight, and as long as we succeed in the counterattack, the enemy will not be able to block the connection between our tunnel and the position of the main peak in the rear; But now we have begun to manage and use ammunition, water, medicine, food and other materials in a unified manner and use them more sparingly, and all supplies are given priority to the wounded. Li Wenwu spoke.

"The party committee of the division has already sent 10 companies to the 597.9 heights to counterattack, and if we add the counterattack on the 537.7 heights, it is estimated that our army will invest at least 20 companies in counterattacks and defensive operations; if we continue to invest troops to counterattack tonight, think about how long our 45th division can hold out? I think that we will have a few days to retreat to the tunnels and then our tunnel troops will be prepared to fight the enemy in the surface positions independently, until our army is ready for a final counteroffensive; As soon as the situation I just mentioned arises, the enemy will certainly do everything possible to cut off and block the connection between our tunnel troops and the main peak positions in the rear. Zhao Lianfa put forward his own judgment.

"We sent sharpshooters to guard the ..... at the mouth of the tunnel",

"I agree with Lian Commander Zhao's statement.....",

"I agree with Company Commander Zhao's statement....."

"In tonight's counterattack, we will cooperate with our fraternal troops to knock out the enemy's firepower points..... At the meeting on summarizing and discussing tactics, everyone spoke enthusiastically and actively offered suggestions and suggestions, which played a role that cannot be underestimated for our tunnel troops to sum up their deficiencies in a timely manner, to deal with them with superb tactics at all times, and to defeat the enemy armed to the teeth.

After a one-hour meeting, the tunnel troops reached the following consensus: 1. Further strengthen the protection of the tunnel.

2. Immediately make all preparations to cooperate with the fraternal troops in the evening counterattack. 3. Unified management of war materials, medical supplies, food, and water, and further saving the use of materials, especially medicines, food, and water; At the same time, priority is given to the supply of the wounded.

4. Be prepared for the worst scenario of being cut off by the enemy and blocking the connection with the main peak positions in the rear. 5. Be prepared to send people out of the tunnel at night to attack the enemy and discuss relevant tactics.

The troops in the tunnel are stepping up preparations for the upcoming counterattack at night, and every cadre and soldier is waiting for the artillery fire of the volunteer counterattack; A new counterattack by the Volunteer Army is about to begin......