After the advance team arrived at Yongan Port, they immediately conducted a careful survey of the landing environment here. According to the hydrological records of later generations, the average depth of the cargo wharves built in this place is more than 10 meters, which is considered a deep-water port with good hydrological conditions. The beach along the coast is more than two kilometers long, and it has a very wide landing surface, so even hundreds of boats can land here at the same time. Although it is unlikely that the Haihan militia will build a permanent wharf here, as long as a few sturdy wooden trestle bridges are built on the shore, the conditions required for landing can be basically satisfied.

However, to the surprise of the advance team, the North Vietnamese army did not send personnel to garrison such a strategic place that was valued by the Military Police Department. Perhaps this was because the North Vietnamese considered the narrow beach, surrounded by hills, to be unfortified, or perhaps because they believed that their adversary's naval power was not yet worth deploying troops to defend the coastline behind the battle line.

Mu Xiabai and Feng Anan each took a few sappers to two mountain passes leading to the outside world to conduct field surveys, and selected the construction sites of the wharf, barracks and material warehouses near the shore. Beyond the two mountain passes there is a meandering river, and within four or five miles to the south are plains and marshes washed by this meandering river over a long period of history, and it seems that the conditions of passage in this place are very poor whether it is going south or north.

However, this is exactly what the Military Police Department wants, this is only a logistics supply base for this military operation, and what is needed is to rely on the dangerous terrain here to reduce the pressure on defenses, and the Military Police Department wants to have swampy land from here to the war zone to the south. The projection of troops does not need to rely on land, but can be carried out by sea, which is only a dozen nautical miles away from the coastline of the war zone, and it only takes less than half a day for sea ships to sail through slowly.

Mu Feng and the others left a few sappers to go to these hills to find a commanding height and a suitable place to set up a lookout post, while they continued to sail south to the war zone. After sailing south along the coastline, they finally saw what they expected: the coast was densely packed with tents and shacks, and in some places there were military flags of different colors, which seemed to be the headquarters of the North Vietnamese army.

However, it is more figurative to say that this is not so much a military station as a refugee camp. These tens of thousands of troops are stationed here, but they are piled up in the east and in the west, there are no walls or trenches, and there is no encampment at all. Although squads of patrolling soldiers can be seen walking back and forth between the camps, if such a camp encounters an attack by a foreign enemy or other emergency, it is feared that it will immediately fall into chaos.

Since the ship of the advance party came from the north, it did not cause much commotion, and after docking, the envoy accompanying him showed the officers who came to inquire the documents and identification documents from the Qing royal palace, and immediately someone took them to the barracks of the Chinese army to meet the local supreme commander.

After entering the Chinese army, the perception of the two changed slightly, the military camp here is at least arranged in accordance with the regular way of camping, the trenches and drainage channels outside the camp to resist the enemy are readily available, the road to enter the Chinese army is full of horses and deer, the tents in the camp are also arranged in rows and rows relatively neatly, there is enough fire spacing in the middle of each army, and the military appearance of the soldiers in the battalion is much better than the troops seen before.

"It seems that the people stationed on the periphery are probably all peasant soldiers. Feng Anan muttered softly.

Mu Shabai also responded softly: "The regular army of North Vietnam still has some combat effectiveness, after all, it has fought with the Yuan and Ming dynasties for hundreds of years, and the troops of the two empires have been pitted in a row, and there is still a heritage as an army." ”

"But it doesn't seem like their regular army is too many, and based on what we've seen before, it's estimated that the regular army only accounts for about one-fifth, right?" Feng Annan began to calculate the actual combat effectiveness of the North Vietnamese army as he walked.

Mu Shabai obviously had his own opinion on this, shook his head and said: "The army we see here is only a part, the real main force should be mostly stationed on the battle line, and their regular army must be more numerous than what we see now." ”

Mu Shabai's unintentional speculation is very close to the facts, the military camp here is actually considered the rear in the current war situation, and the combat zone in the south is more than ten miles deep, and tens of thousands of North Vietnamese regular troops and a number of peasant soldiers are deployed in this combat zone.

The officer who led the way took them outside the tent of the Chinese army, and handed over the generals and soldiers who were stationed here. The North Vietnamese envoy handed over the military order of the Qing royal palace, Zheng Zheng's personal letter, and his own identity certificate to the personal soldier, and after a while, the personal soldier came out to send a message to let them in.

As a powerful family that controls the military and political power of North Vietnam, the supreme commander of the North Vietnamese army in the local area is also from the Zheng family, and this general named Zheng Bai should be Zheng Zheng's distant cousin, in his forties, dark and strong, with a martial temperament. After the envoy introduced Mu Feng and the others, Zheng Bai invited the two to sit down.

"The letter of the eldest prince has already been read below. Since it is the meaning of the Qingdu Palace, if the two generals have any requirements, they will definitely cooperate fully. Zheng Bai's attitude was very upright, and he directly said it very clearly as soon as he came up. Although he is a high-ranking military general, he only plays the role of a thug in the Zheng family's system, and he knows very well who to obey.

It had been three months since the Trung clan had reached an arms trade agreement with the Haihan people, and it was no longer a secret within the North Vietnamese military, and many of the military personnel sent to the Tu Son training camp for military training were the sons of the Trung family, and the second son of Trung Bai was also one of the first officers to be trained. It was the first time for Zheng Bai himself to deal directly with Haihan, and the reason why he was so humble was because those two letters worked.

The document from the Qing royal palace was written by King Zheng of Qingdu, the actual controller of the current North Vietnamese regime, to the effect that Zheng Bai should act in accordance with the intentions of the Haihan people, and that the Haihan people could be given full autonomy in combat, and if necessary, let the Haihan army undertake the main task of defense or counterattack. This letter was written by Zheng before Zheng Zheng left, and if the cooperation between the two sides collapsed, then the letter would naturally be destroyed, and if the two sides reached an agreement to borrow troops, then Zheng's envoy would rush to the war zone in advance with this letter, so that the two sides could coordinate the combat system.

In addition to being more time-sensitive, the letter from Zheng Zheng was also more detailed, detailing the Haihan's intentions to send troops and the things that might require Zheng Bai's cooperation. Of course, Zheng Zheng's move also has the intention of stabilizing the morale of the army, and in the tense situation of the war, the reinforcements of the soldiers in front of the company will soon arrive, which is undoubtedly a great good news, not to mention that this support army is still from the Haihan people who are said to be quite capable of fighting.

Of course, Zheng Zheng did not talk about the specific terms of the transaction between the two parties in the letter. This kind of hiring foreign armed forces to intervene in the civil war in the country is not a glorious thing after all, and the fewer people who know about it, the better. Moreover, the two sides have also agreed that the Haihan troops will not identify themselves when fighting abroad, but will directly fight under the banner of the North Vietnamese army. In fact, the military police department did not want to expose its military strength to the outside world too early, so the two sides hit it off and quickly reached an agreement on this issue.

"General Zheng, we'll talk about the specific requirements later, so please tell us about the current battle situation first!" Mu Xiabai was not in a hurry to list the requirements of the Military Police Department one by one, but planned to understand the trend of the battle situation first.

Zheng Bai nodded and said, "Then it's better to be respectful than to obey your fate!"

At present, some soldiers have propped up a three-foot map with a wooden frame, which depicts the terrain of the east coast of Vietnam, but due to the current level of surveying and mapping, the resolution of this map is indeed a bit miserable. In Mu Feng's opinion, the angle of view of this map is at least 200 kilometers above sea level, and there are no details at all, the land distance from Yong'an Port to here is close to 10 kilometers, and it is only 1 centimeter on this map, almost 1:1000000 scale, where can we talk about discussing tactics and arranging positions?

At that moment, Feng Anan said: "Please wait a minute, General Zheng, this map of yours is not very easy to use, let's use the map we brought!" After that, he took out a folded map from the briefcase he carried, opened it and fixed it to the wooden shelf.

"This ...... This is the ...... "Zheng Bai is also a person who leads troops to fight, and at a glance, he knows that the map of the Haihan people is indeed not the same grade as what he has in his hand.

The map Feng Annan took out was a military map based on the enlarged 3D satellite map in the large database, and the scale was dozens of times larger than Zheng Bai's map, and even marked the direction of the mountain range and the location of the commanding heights in this area with clear contour lines.

After the base camp decided to take military action to intervene in the civil war in Annam, the Military Police Department hurriedly mobilized technical forces to make military maps of the east coast of Vietnam, especially in the war zone. And the Military Police Department continues to work overtime to produce larger scale details, which will be sent together as war materiel.

But even this map, which is still relatively small in scale, has already made Zheng Bai stunned: "You guys...... Where did you get ......?"

"Where did we get the map is not the point, General Zheng, our current combat mission is to unite with the outside world, and we are your allies and not enemies. We are here because the prospects for your war are no longer optimistic, and our mission here is to help you win this war, and your task now is to explain the current situation to us as clearly as possible, so that we can make a plan for the war as best we can. Can you understand what I said?" Mu Xiabai didn't give Zheng Bai a chance to question himself at all, and immediately blocked his mouth with words.

Zheng Bai hesitated for a moment before he nodded and said, "I understand." But this map ...... Can you have a copy of the military Chinese book copied later?"

"Yes. Mu Shabai replied: "Now let's get down to business!"

"Okay, okay, get down to business!" Zheng Bai quickly returned his attention to the front of him and explained to the two of them the changes in the battle situation in the recent period.

Three months ago, that is, when Zheng Zheng and Tao Dong came to discuss arms dealing, the shape of North Vietnam was still very good, and the army led by Zheng Bai had already attacked Quang Tri, which was only a hundred miles away from Hue Province, the base of the Nguyen clan in South Vietnam, and it seemed that it was only a matter of time before the soldiers came to Hue to capture the Nguyen rebels. But it was at this juncture that South Vietnamese firearms units appeared on the battlefield without warning, and in the first battle, more than 3,000 North Vietnamese vanguard troops were killed and wounded.

From then on, the tide of battle began to turn, and the South Vietnamese rebels, armed with a large number of arquebuses and a few guns, launched a counterattack, while the North Vietnamese army, still in the cold weapon, was almost helpless against this "sharp" attack, and suffered heavy casualties. In desperation, Zheng Bai could only command the troops to fight and retreat all the way, and retreated to Donghai, which was 150 miles away, before relying on the Donghai River that entered the sea from here to stabilize the situation.

Dong Hai this place in the later generations of Feng Ya Ji Bang National Park, the scenery is still quite good, but the North Vietnamese troops retreated here did not have time to enjoy the scenery, only three days later, the South Vietnamese army successfully smuggled from the upper reaches of the Dong Hai River, and once again drove the North Vietnamese army north. And this retreat, then retreated more than 100 miles to the north, and it was not until the current front that it really stabilized its position.

However, it was evident that the South Vietnamese had made adequate preparations for this counterattack, and the size of the troops pursuing them all the way north was better than the day by day, and it was said that there were already 100,000 troops by the time they reached this point, which was certainly not a phenomenon that could be explained by the improvised counterattack. With only 20,000 regular troops and almost the same number of peasants and civilians left on the North Vietnamese side, they could barely resist the daily attacks of their opponents by relying on the dangerous terrain in the vicinity under the strict order of Thang Long Province not to continue to retreat. Although there is no sign of another rout for the time being, even if it continues to be consumed slowly, the tens of thousands of North Vietnamese will sooner or later be consumed alive on this battlefield.

Mu Xiabai and Feng Anan glanced at each other, and the same thought turned in their hearts. It is no wonder that the Zheng clan in the north will be in a hurry, preparing to levy all the households near Thang Long Province as peasant soldiers and then go south, it seems that they are planning to bet on all their net worth, and directly stud with the Nguyen clan in South Vietnam. And Zheng Bai's attitude is so good, I'm afraid that he has been hoping that the reinforcements from the north will arrive early.

"General Zheng, how your army is currently arranging its defensive positions, can you tell us in detail?" Mu Xiabai had already put away his previous relaxed feeling and asked Zheng Bai very strictly.

Zheng Bai pointed to the map and explained: "According to the topography of this place, the defense line is arranged into three layers ......."

To the south of the North Vietnamese army was a mountainous area that isolated the South Vietnamese army. If the South Vietnamese army wanted to get around, it would have to march westward, hundreds of miles more from the dense forest, a march that would be a nightmare for an army of more than 100,000 men, and the supply lines through the primeval forest alone would be enough to collapse the logistical baggage force.

Because of this, although the several passes guarded by the North Vietnamese were difficult to attack, the South Vietnamese army still did not hesitate to suffer casualties, and continued to attack the North Vietnamese defense line every day, preparing to grind this battle hard with human tactics, and the South Vietnamese Nguyen Clan also knew very well that after passing this pass, there would be no more obstacles to further north to Thang Long Province, and they could push all the way through.

At present, among the three layers of defense line arranged by Zheng Bai, the first layer of defense line has been broken through the South Vietnamese offensive for several days, and the North Vietnamese troops have retreated to the second layer of defense line. As for how long this line of defense can last, even Zheng Bai himself doesn't have a sure time in his heart.

"I think, let's go directly to the frontline position to see the real situation, right?" Feng Annan listened for a long time, and could only hear a rough idea, a certain mountain pass is arranged with a number of infantry, archers, and spearmen, but this kind of explanation is really difficult to understand, and it can only be made up by the brain, so there is no way to complete the reconnaissance task undertaken by the advance team.

"The two generals are burdened with heavy responsibilities, how can they be in danger?" Zheng Bai was shocked when he heard this, and hurriedly dissuaded.

Zheng Zheng made it very clear to him in his letter that the two Haihan people who came to the front station this time were the leaders of the Tushan training camp and were also the "senior officers" in the Haihan army. As for how senior it is, Zheng Zheng can't figure out Haihan's military position, so he can only call Mu Feng "general" and the two can be sent by Haihan people to be military leaders, which is definitely not a small role. In his letter, Zheng Zheng ordered Zheng Bai to protect these two men, because if something happened to them on the front line, it might make Haihan's military aid plan fall back.

"General Zheng, everyone is a soldier, needless to say, let's not talk about hypocrisy, we are not here to enjoy the mountains and rivers. In a few days, our Haihan troops will come over, and if we don't make preparations first, then our comrades-in-arms and soldiers will pay the price for it! This is not what we want to see, we are here to win the battle!" said Mu Shabai in a loud voice.

"In that case...... Someone!" Zheng Bai gave an order, and immediately a personal soldier stepped forward to obey the order.

"Go get two sets of armor for the two generals!" After Zheng Zheng finished the order, as if he expected that Mu Feng and the others might refuse, he immediately turned his head and persuaded them: "Swords and guns have no eyes, be prepared, although the two generals are brave, but since they are going to the front line in person, they must wear armor to go into battle according to military regulations!"