Fortunately, the four cavalry of the "Security Army" who were responsible for "escorting" the envoy of Yeluxian were all veterans of a hundred battles, although the incident happened suddenly, although everyone was a little absent-minded at the beginning, but as the people at the head of the city said the land of Bohai and the words of recovering the country, the four cavalry of the "Security Army" were already alert, and when the defender of the city ordered to open his bow and arrows, the cavalry on the right side of the "messenger" had reached out to pull the reins of the former's horse, who was still in a state of astonishment, and was ready to take him out of danger. The other two cavalrymen removed their shields from their saddles as fast as they could, providing cover for their companions and the Heralds—even if the small cavalry shields provided limited protection. The cavalry company commander of the "Security Army" who led the team took off his shield to block the arrows, raised his signal gun, and pulled the trigger in the direction of the shouting sound from the city just now.

First, several "escort" cavalry reacted quickly, and secondly, the flares hit the battlements of the city walls, producing violent flashes and scorching flames, affecting the aiming of the archers on the city. Therefore, although the defenders who came to their senses fired a flurry of arrows, they were unable to hurt the "messenger" and the four "security army" cavalrymen in charge of "escorting".

After galloping nearly a hundred paces in one breath and completely out of the effective range of the bow and arrow, the cavalry company commander of the "Security Army" who led the team took the mount. While arranging for two of his men to escort the "Herald's Messenger" back to his headquarters, he took out another flare from his bosom and fired a red flare into the sky that represented the failure of persuasion and the need for a strong attack.

In fact, there was no need for the commander of the cavalry company of the "Security Army" to send a signal, and what happened up and down the north gate of Xin'an City was enough to explain everything. Therefore, the commander of the cavalry company of the "Security Army" here pulled the trigger of the signal gun, and more than a dozen light and heavy machine guns of the 1st Battalion of the 1st Marine Regiment of the "Flying Dragon Army" who were responsible for covering the situation had already opened fire. The dense bullets not only knocked down the Bohai defenders who poked out of the battlements to draw bows and shoot arrows, but also smashed the city wall and the small tower on the city wall to pieces. Immediately afterwards, the battalion's ten 60mm and 82mm mortars also opened fire, and in a matter of moments, the tower and the city wall to the left of the tower were completely enveloped in smoke and flames.

Although there has been no fighting since Liaoyang City went south, the relevant battle plan is very perfect. Therefore, as Yeluxian's "Sacred Decree of Dedication to the City" lost its effect, a fierce battle of attack and defense of the city began. In front of the 20,000 Zhou troops armed to the teeth, the soldiers with a circumference of only five or six miles, a population of less than 10,000, and soldiers who can hold swords and guns, and a young and strong man of no more than 2,000 people, can be regarded as a real projectile land. Therefore, the fire counterattack carried out by the 1st Battalion of the 1st Marine Regiment in order to cover the "messenger of the message" has already emptied the head of the city near the north gate of Xin'an City. When the "southbound cluster" surrounded the entire Xin'an City, and the eighteen 130mm siege guns of its siege artillery battalion blew four or five gaps in the northern wall of Xin'an City with two salvos, the entire Beicheng City could not even see the shadow of a defender. However, Zou Zhenyuan did not take it lightly. Because he knew very well that destroying the city wall and occupying the head of the city was not a difficult task for the Zhou army, which had absolute firepower superiority, but the real test was in the city and in the street fighting. Although Xin'an City is much smaller than the previous Changba City and Fengzhou City, and the number of defenders is also much smaller, after all, the other party has the advantage of geography, people and people, and if the Zhou army advances lightly, it is likely to suffer many unnecessary losses. Therefore, Zou Zhenyuan repeatedly told the deputy commander of the 15th Infantry Regiment of the Fifth Composite Infantry Division of the "Flying Dragon Army," who was responsible for leading the army into the city, to be cautious and not to underestimate the enemy. At the same time, he also very simply rejected the request of Xing Zhengnan, who was aroused by the sound of gunfire, to serve as the commander of the first echelon of the siege, and only allowed him to stand on the tall watchtower behind the second echelon of the siege and understand the battle situation in the city through a telescope. In this regard, although Xing Zhengnan was unwilling, he did not dare to disobey the military order in wartime, so he had to stand obediently behind and enjoy it through the lens of the telescope.

As it turned out, Zou Zhenyuan's caution was completely correct. The Northern Expedition, which lasted for more than three months, not only allowed the Zhou army to achieve brilliant results, but also taught his opponents many experiences and lessons in dealing with them. Seeing that his surprise attack failed to hurt the so-called "messenger of the decree", and that the counterattack of the Zhou army was extremely fierce, he immediately ordered the surviving soldiers on the city to be withdrawn and scattered to various parts of the city with other men and horses, preparing to rely on the pre-built barricades, trenches and other defensive facilities to make a final decisive battle with the Zhou army that rushed into the city.

With preset blocking positions, crossbowmen in almost all advantageous positions in the city, and the brave spirit of looking at death for the sake of recovering the country, the small Ningzhou Xin'an City, with only 2,000 poorly trained and averagely equipped defenders, fought with the Zhou army for most of the day with enthusiasm, and fought from the beginning of the morning to the end of the evening before being completely wiped out by the opponent who had an absolute advantage in troops, firepower, equipment, and training. For this, the Zhou army paid more than 200 casualties, but what was obtained was a small city full of devastation and ruins.

The tenacity of the Bohai defenders, the difficulty of the siege process, and the imbalance between investment and harvest made Zou Zhenyuan, who stood on the broken city wall of the north gate of Xin'an City in Ningzhou and watched the situation of the whole city, not only did not have any joy of breaking the city, but was a little worried. If Fuzhou and Suzhou in the south of Ningzhou and Zhenhaifu and Muzhou in the east were also in such trouble, not only would the end of the entire Northern Expedition be delayed, but it would also affect the inspection and protection of the original border between Liao and Goryeo. Therefore, Zou Zhenyuan ordered his subordinates to complete the work of cleaning up the battlefield and pacifying the people as soon as possible, and on the other hand, he ordered to intensify the interrogation of the captured Bohai defenders, in order to get from these people the reason for the sudden confrontation between the Bohai people and the Zhou army, as well as the authenticity of the so-called "Bohai restoration" of the Xin'an city defender.

It turns out that there are soft bones in any nation or tribe. After a surprise interrogation, the relevant information was quickly sent to Zou Zhenyuan's hands.

According to the prisoners' confessions, the behavior of the Bohai people in Xin'an City, Ningzhou, against the Zhou army was completely planned and premeditated. It is likely that the mastermind behind it is Da Guangxian, the son of the former King of Bohai and the deceased monarch Da Jiuxian, who is currently under the wing of the Goryeo and has changed his name to Wang Ji. Moreover, it was not only Ningzhou that was encouraged by Wang Ji (Da Guangxian) to participate in the so-called "Bohai Restoration", but also Fuzhou and Suzhou in the south, Zhenhaifu and Muzhou in the east, and other former Bohai hometowns with a relatively large number of Bohai people. In fact, even the prefectures and counties such as Concubinezhou, Haizhou, Yaozhou, and Chenzhou, which he had easily received before, also had Wang Ji's (Da Guangxian)'s cronies and henchmen active. It was only the latter that the proportion of Bohai people was relatively low and could not form enough power, so they had to temporarily hibernate to wait for the situation to change.

Although the captured Bohai people were unable to access the more core secrets due to their low official ranks, they could not provide the entire conspiracy of Wang Ji's (Da Guangxian) so-called "Bohai Restoration" operation. But the news obtained so far is enough to make Zou Zhenyuan's heart tremble. First, since Wang Ji (Da Guangxian) had connected almost the entire Bohai remnants on the Liaodong Peninsula, his southward reception was bound to be full of resistance, even if he could rely on the strong strength of the Zhou army to temporarily suppress the resistance of the Bohai people, it would not be easy for the imperial court to govern these areas in the future. Second, since Wang Ji (Da Guangxian) was able to connect the remnants of the Bohai Sea on the Liaodong Peninsula, it cannot be ruled out that he would also send people to incite the remnants of the Bohai Sea in the prefectures and counties north of Liaoyang City and in the prefectures and counties of the former Tokyo Province of the Liao Kingdom to participate in his so-called conspiracy of "restoring the country to the Bohai Sea". Although the number of Bohai people in these prefectures and counties is not the majority, it is definitely a trouble for the local government to make trouble. More importantly, once the Bohai people make trouble, it will inevitably make those Khitans who are unwilling to destroy the Liao State, those Jurchens who disobey and waver to the Later Zhou court, and the pro-Khitan Han people who are unwilling to lose their former powerful positions and want to continue to enjoy the previous high-ranking officials and Houlu are ready to make trouble and take the opportunity to make trouble. In other words, if Wang Ji's so-called "Bohai restoration" conspiracy was not handled well, the victory of the Northern Expedition, which was fought by 150,000 Zhou troops for more than three months, would be greatly reduced, and even lay many hidden dangers for the future Zhou court's rule here, plunging the Liaodong Peninsula and even the entire former Tokyo Province into long-term turmoil and chaos.

Therefore, after receiving the relevant interrogation results, Zou Zhenyuan immediately sent a fast horse to inform the Huanghai in Liaoyang City of the relevant situation and his own opinions, and immediately telegraphed Kaifeng through his hand and submitted it to the committee for decision.

After discussion, Wang Kunjun and others agreed on the one hand that Zou Zhenyuan's troops should be divided into two routes, and that a rapid force should be sent to the front line of the Yalushui (Yalu River) immediately to inspect the border between the former Liao State and Goryeo, so as to prevent Wang Ji (Daguangxian), who was hiding in Goryeo, from taking risks and directly sending troops to Liaodong to disturb the situation, and also to prevent the Goryeo people from taking advantage of the chaos to advance northward and encroach on the territory of the former Liao State. On the other hand, it instructed the Intelligence Department to make every effort to find out about Wang Ji (Da Guangxian) and the so-called "Bohai Restoration" at all intelligence stations in the former Liao Kingdom's Tokyo Province and in Goryeo, with a view to grasping his conspiracy in the shortest possible time, and to closely monitor the leading figures of the Bohai people in the major prefectures and counties to prevent them from provoking incidents and disturbing local order, so as to echo Wang Ji (Da Guangxian) from afar.

After receiving the committee's order, the intelligence department's sub-stations in the former Tokyo Province naturally took immediate action and made every effort to find out the news. Zou Zhenyuan also immediately divided his headquarters into two, with the 15th Regiment of the Fifth Composite Infantry Division of the "Feilong Army", the cavalry regiment under the division, the infantry regiment of the "Security Army", and one regiment of cavalry to form a temporary border patrol and protection brigade with a total strength of nearly 10,000 people. He himself led the remaining men and horses of the "Southern Strike and Border Patrol Protection Cluster" to continue southward after joining up with the 14th Regiment of the Fifth Composite Infantry Division of the "Feilong Army" and the two infantry regiments of the "Security Army" reinforced from Liaoyang City, and continued to move south, completing the acceptance of the remaining states and counties on the Liaodong Peninsula by forceful means.