Poison gas, this is the biggest headache for Dong Ku at present. Attacking the pit is not good for recruits, their reflexes and ability to withstand pressure are weaker than those of veterans.

If you attack all the way and use bomb grenades, it is not that you can't take these tunnels, but you will suffer heavy losses, and you will not be able to stop the opponent from venting poison gas.

As soon as the poison gas came out, none of their soldiers in the tunnel could come back alive, even if there was an oxygen tank that could breathe independently, but the oxygen tank could not insist on cleaning the nearly five-kilometer-long aisle, needless to say, it was not possible. Moreover, poisonous gas is not only breathing, but also attached, and can poison people as well as on the skin.

"Go down and clear the aisle and draw the structure in detail."

After Dong Ku gave the order, he returned to the headquarters with Zhang Long and Li Ruide.

All the high-level officials already knew the results of the road, and the poisonous gas bomb inside would be the biggest obstacle to their attack. Once the battle is urgent, the Japanese troops in the tunnel will be killed, and this line of defense is destined to throw away the lives of the soldiers and suffer heavy losses.

There is no way for the Japanese army to retreat here, and they will jump off the wall at any time. And later, the Japanese army can also use poison gas, and when the battle is reached on this point, it is no longer effective to kill a civilian ten times, either you die or I die, who will pay attention to the means? Moreover, it is the two warring parties, and the means of killing the enemy on the battlefield are all the best, which is also a headache for Dong Ku.

Back at the headquarters, Zhang Long and Li Ruide cleaned the wounds with the help of the hygienist, and quickly drew the general tunnel structure and defense system with the help of memory.

As the general appearance of the tunnel appeared, Dong Ku's brows were tightened, and Zuo Boyang and Liu Chengcheng were also serious.

This tunnel is divided into several parts, the first of which is a dead end, which is a pit to kill the enemies who enter it, except for violent destruction. There is no other way.

The second part is a road, which leads to the rear and is the main tunnel. Zhang Long did not search for all the interlayers in the tunnel, and they did not know the specific setting of the tunnel. The third part is the side mezzanine of the main tunnel, which contains poisonous gas bombs and has a hidden grid. There are mechanisms, not only can you block the enemy who enters the main tunnel, but you can also fight in the mezzanine or dark compartment in your own tunnel, and the poison gas bombs are also in these dark compartments, if it weren't for Zhang Long's several grenades exploding together, stunning the Japanese soldiers inside, two people, one always has a chance to detonate the poison gas bomb.

This is also the most troublesome, with powerful blasts all the way. When the army poured in, and the Japanese army could not resist, it would let the Japanese army hiding in the innermost part detonate the poison gas bomb.

Although it was possible to use a feint to force the Japanese to release poison gas, who could guarantee when they would release it? According to Zhang Long's description, two people with 200 catties of water and food can survive quietly in the mezzanine for a month, and it is difficult to trap them. Moreover. The reservoir of the main tunnel has enough tons of water. There are a few of them, and if they are not completely captured, it will be difficult to determine how long the Japanese army will survive in them.

Again, the exact location of the gas bomb on it, how many, this cannot be determined at this time. Even if this tunnel is fully controlled and the detailed structure is drawn, it is uncertain what is going on inside the other tunnels.

Judging from the ylang-ylang incense coming out of the ground, with lack of oxygen, throw gas bombs. It is difficult to work, as long as a passage is blocked, the exhaust system will drain the gas in the tunnel.

Saeki raised his head in contemplation and said: "Captain, at present, it is indeed easy to defend and difficult to attack, there are fewer people, it is difficult to clean up all the passages, there are too many people, and it is not easy to deal with the Japanese army's jade burning. ”

Fire attack?

Everyone looked up at him.

The role of the flamethrower has been tried before, the Japanese army can hide in the tunnel, in the mezzanine, can move, even if you find the firing port, you burn it here, he hides far away there, and he will come back when he turns around. The two tunnels attacked together, but they could not block the dark grid in the mezzanine of the tunnels, nor could they control the release of poison gas by the Japanese army.

Seeing everyone's doubts, Zuo Boyang said in a good time: "We can control the front end of the main tunnel and the interlayer at the same time, blow up the Unicom with explosives, pour gasoline into the tunnel, the number is more, these tunnels attack at the same time, roll into the oil drum, in this way, the gasoline explodes and burns, at least half of the tunnel will be cleaned out, we don't go in to clean up, find the exhaust port here, so that the smoke inside can't come out, even if his ventilation system is independent, it can't provide enough oxygen to the tunnel, and he is willing to release the gas bomb, Just hold it inside and enjoy it yourself, we find all the vents and seal them so that they don't leak out. ”

"Good way!"

Everyone's eyes lit up.

This is indeed a good way, the air in the air circulation, to provide enough oxygen for combustion, so that the gasoline can be fully burned, not only to raise the temperature in the tunnel, to evacuate the oxygen, but also to burn those Japanese soldiers by overheating.

Dong Ku listened but nodded, he was not only thinking about killing the Japanese soldiers inside, he was thinking about those poison gas bombs once the Japanese army knew that they could not survive and the dog jumped over the wall and detonated, it would inevitably pollute this piece of land for decades.

Although these are difficult to control in the war, this is the land of their own country, and the disasters that have been left behind for decades can be avoided or avoided.

Those gas bombs are generally difficult to detonate, because of the fuse, do not touch, do not burn, the problem is not big, the shock is difficult to detonate these gas bombs.

It can be burned with fire, the poison gas bomb is in the mezzanine, the Japanese army dog jumps over the wall, the jade is burned, there is enough time to detonate the poison gas bomb, and furthermore, if you want to incinerate all the tunnels several kilometers long with oil, the oil required is not a small number, and it is difficult for him to come up with too much oil for incineration only by relying on the oil fields here in Anda.

In addition, once the Japanese army found that the oil was coming in, knowing the intention of the advance army, they had a fire door in the tunnel to block a section of the tunnel, which could ensure that it would not be burned by flames, so it was still difficult to complete the cleanup.

After listening to Dong Ku's analysis, everyone felt that it made sense. The Japanese army will not ignore the fire attack, those iron gates wrapped in asbestos are enough to block the flames, and they will still have living space inside, unless the oil can quickly flow into the middle of the tunnel, and once it explodes, the entire tunnel will be wrapped in flames, which can achieve the purpose of clearing the tunnel at one time.

However, if the enemy blocks part of the tunnel, they will lead you before setting fire to this side, but they will still not be able to meet the requirements of cleaning the inside, and there may be no way to dodge, and the flames erupting from this end will cause damage to the approaching soldiers.

Dong Ku took a deep breath, he really didn't know how to do this seemingly stalemate battle.

Zuo Boyang's strategy should be said to be the best plan except for the fear that the Japanese dogs jumped over the wall in a hurry and detonated the poison gas bomb. Although the fuel consumption will be huge, it is not a big deal to be able to reduce casualties, at most the follow-up attack, not all the mecha troops are just that, the infantry attack, for the current Japanese army, still can't stop his progress.

After pondering for a while, Dong Ku really couldn't think of a good way, he raised his head and said, "At present, apart from Adjutant Zuo's suggestion, is there any better way for everyone to love?" ”

Everyone shook their heads. This kind of defense is not something that can be used by artillery tanks, except for the hard bombs, the fire attack seems to be faster, and it seems that there is no good way to replace it.

"Okay, for the time being, take Adjutant Zuo's suggestion, sir, you are responsible for transporting oil, mainly gasoline, gasoline burns more violently, can make the fire area larger, if not, we will quickly grunt the oil drum into it, close the hole, leave the director bomb to detonate, and clean up section by section."

"It's good."

Liu Chengcheng had no objections, picked up the phone and ordered to transfer the gasoline from Harbin and prepare for the attack.

"All units withdraw, the order to attack is canceled, wait for the tunnel to be completely cleared, blow up the entrance, prevent the Japanese from entering and inspecting, and detonate the poison gas bomb in advance."

"Yes!"

Qu Jun just began to deploy.

Sun Tao is the commander of the group, he doesn't have to ask about these small things, and he is still thinking about what way to quickly take down the tunnel when everyone ordered all departments to withdraw to the defense area and prepare to rest overnight.

"If the gasoline can flow quickly, even in the middle of the section, the air combustion can burn the Japanese troops in the tunnel at one time, and I am afraid that the high temperature will blow up the poison gas bomb."

He muttered alone.

Others have given up thinking because there is really no better way.

Dong Ku's ear power is quite good, and Sun Tao's muttered words reached his ears without any mistakes.

Air combustion......

He remembered that gasoline volatilized, and gases could be burned, and it was indeed what Sun Tao said, which could ignite gasoline in the air from the oil surface.

These do not solve the current problem, the concentration of volatile gasoline in the air will cause air combustion when it reaches a certain level, but there must be enough gasoline to volatilize! Besides, the temperature inside the cave is not low, much warmer than the outside, but it can't reach the temperature of rapid volatilization, so the concentration in the air will not reach the level of combustion so quickly.

If you want to talk about the same air combustion, or air explosion, Dong Ku knows that there is one way, and that is dust. Combustible flocculent dust or particles, after reaching a certain concentration in the air, once ignited, it will cause an air explosion, the equivalent is determined according to the dust concentration and coverage area, such as flax factory, which in the eight years of the dust treatment is not very concerned about the era, a flax factory covering an area of several hundred acres, an explosion will be razed to the ground, indiscriminately kill all life, the ignited part is not much, but the later fire head is not extinguished, and then continue to burn, in fact, the destruction of the flax factory is the explosion, not the fire.

Air Explosion ......

Dong Ku was about to leave the headquarters, but suddenly stopped his feet.

A flash of inspiration flashed in his mind, and his eyes lit up with the sound of various substances that exploded in the air.

"With that, we can destroy these secret tunnels at once and blow up the Japanese soldiers inside without wasting fuel." (To be continued......)