Sizzling——

The intercoms of everyone in the duty room rang with the same voice.

"Zombies! Here they come!"

Xiao Hu shouted loudly.

Unlike Guo Peng and Zhu Xiaosuo, Xiao Hu has been stationed at Da Zhangshu Base since he was promoted to outer city personnel and rarely goes out.

Hearing this voice, Li Yu's face changed slightly.

Walked out quickly.

At this time, three hours had passed since the heavy fog hit.

Under the influence of the heavy fog, zombies came out of the dark corners where they had taken refuge.

Heavy fog is essentially a large number of small water droplets or small ice crystals suspended in the air near the ground.

Zombies like water and humidity. In an environment with such high air humidity, zombies all ran out and headed to popular gathering places.

The Dazhangshu Base has a population of several thousand at this time and is the most popular place within a radius of 100 kilometers.

Zombies are attacking.

These zombies are pouring towards the direction of the Da Zhangshu base.

And at this time.

Hundreds of zombies have gathered under the outer city wall.

As Zhongshi Yang and others sprayed with liquid nitrogen, light rain fell. Although the zombies and the ground could be seen clearly under the illumination of the searchlight, these zombies also became more excited.

Stimulated by the rain, these zombies kept roaring.

"Ho ho ho!"

Li Yu just glanced at it and ignored it.

Because he knew that these zombies wouldn't cause much trouble, the three-story mobile gate was opened and these zombies could not break in.

What's more, if it's really desperate, you can also use a drone to hoist zombie-attracting chemicals to temporarily lure the zombies away.

Since the establishment of the Da Zhangshu base, my uncle has been the chief of defense at the base and is now also the deputy minister of the Department of Military Preparedness, so he still has some research on it.

He anticipated various situations, so while patrolling outside, he found a thousand-year-old pagoda in Tianhua Mountain about ten kilometers away from the Da Zhangshu base.

This ancient pagoda is indeed wonderful.

It collapsed and was rebuilt, built and collapsed again, over and over again countless times.

Later, ten years ago, the foundation of the tower was made solid with quick concrete, and then the tower was built on top, with a total height of about thirty meters.

The whole building is made of concrete, imitating the texture of wood, and then coated with a layer of raw wood paint.

It still looks like that.

After that, the wind cannot blow it down.

Tianhua Mountain is right at the top of the mountain, with an altitude of nearly one thousand meters.

The area around the Da Zhangshu base is considered to be at a relatively high altitude.

My uncle simply modified the tower, blocked the upward passage, and set up a platform on the top.

Once the heavy rain falls and the mobile gate knife fails, he can also fly the drone here carrying the zombie attracting agent to lure the zombies there and temporarily postpone the zombie siege of the Da Zhangshu base.

However, in this foggy weather, drones cannot fly there.

Li Yu was focusing on this attack at this time. The uncle and the others would deal with the zombies outside.

Thinking about it, he picked up the walkie-talkie and asked Lao Bi: "Lao Bi, are the helicopters ready?"

The reason why that man entered the inner city has been found, and the next step is to follow the clues and dig out the collaborators.

But in the end it was a false alarm. This time the incident did not involve people from the inner and outer cities, otherwise it would be even more troublesome.

Lao Bi was in the Second Outer City at this time. Looking at the huge helicopter in front of him, he quickly replied: "City Lord, we are ready, but..."

"It's just that it's easy to take off but difficult to land. We've sprayed so much liquid nitrogen here that the view is a little clearer.

But if you fly to Oil City and there is heavy fog there a few hours later, landing will become a problem, and the plane may be destroyed and people may be killed.”

Li Yu frowned and replied: "There is also liquid nitrogen over there in Oil City, and some will be sprayed when the time comes."

Lao Bi sighed and said: "But... even if liquid nitrogen is sprayed in Oil City, it can only reach a maximum of tens of meters. But when a helicopter lands from hundreds of meters or even thousands of meters, the visibility of dozens of meters is not good.

"

"Furthermore, the area of ​​Oil City is smaller than our headquarters, which requires precise landing."

Li Yu thought for a while and suddenly thought of a solution.

So he said: "The helicopter carries liquid nitrogen and then sprays it, wouldn't it be possible to see clearly?"

Spray liquid nitrogen from a high altitude, and the liquid nitrogen will blow farther away, giving the best effect.

Before the end of the world, this method was often used to solve heavy foggy weather, and was also used as a means of artificial rainfall.

"Let's try this. You can load the liquid nitrogen onto the helicopter, fly it in a circle hundreds of meters above our base, and spray it simultaneously. You can give it a try."

After thinking for a while, Li Yu continued:

"You start like this, test it little by little, don't fly so high at first, fly to thirty meters first, and then fly to fifty meters, and then try again, hover, then fly a little higher, spray liquid nitrogen, and test this

Is the method feasible?"

When Lao Bi heard this, he was a little hesitant.

According to Li Yu's method, the operation is too difficult.

If the effect of the liquid nitrogen spray is not satisfactory after the helicopter takes off, it will be difficult for him to land.

However, what Li Yu just said also makes some sense.

If you adopt the method of hovering and flying straight up, even if the effect of liquid nitrogen spraying is not good, it will just fall straight down and stop at the original place.

Thinking of this, Lao Bi finally said: "Okay, let me give it a try."

On the fence.

The second uncle, third uncle and others stood behind Li Yu and heard the conversation between Li Yu and Lao Bi.

The second uncle sighed and said: 'Xiaoyu, in fact, if you really want to take action against the northern border, you can wait until after this foggy natural disaster.'

"It's not safe to be in such a hurry."

"Also, do you think this will work? I asked Lao Xie and the others not to retreat to Oil City for the time being. We will wait for a while and find a rainstorm..."

What the second uncle said made sense, but Li Yu pondered for a while and then said:

"No one knows when the next heavy rain will happen. During this period, people in the north may cause some trouble. Let's deal with it quickly."

After saying that, he hurried to the duty room.

Use the military radio to contact Lao Xie.

"Lao Xie, have you retreated?"

Sizzling——

A full minute passed before news came from the military radio.

There seemed to be some panic over there, and there was constant noise.

"City, City Lord, I just packed up here. The president just told me about it, but he didn't explain the reason clearly. Can you tell me why you have to retreat suddenly? This is too sudden. And our helicopters

We simply can’t take everyone away..."

Li Yu opened his mouth and answered:

"I want to attack the Northern Federation and massacre the city, so you retreat as soon as possible. The reason is very simple. The Northern Territory has sent spies to break into the inner city. The Northern Territory cannot stay. I have asked Ju Tianrui to solve the problem of not enough helicopters.

I have sent all the helicopters to pick you up."

After Lao Xie finished listening, he was silent for a few seconds.

I watched my men around me hurriedly pack up my things and carry them to the helicopter.

He sighed in his heart, originally he wanted to make some achievements here in the north, but he had only been here for a long time before he had to return to the base again.

Helpless, Lao Xie had no choice but to say: "Okay, I understand, I will retreat as soon as possible."

After saying that, he raised his head and asked Lao Yi next to him:

"What's going on over there at Yuan Zhi?"

Lao Yi frowned and said, "He just came here twice and asked us why we suddenly made such a big move. I told him that we had to return to Oil City. The specific reason was not stated."

Lao Xie quickly asked: "You didn't tell him about the fog, did you?"

"No." Lao Yi shook his head.

Lao Xie looked out the window at the clear sky. He could never have imagined that heavy fog would fill this place soon.
To be continued...