After Director Ma gave the order, several people inside quickly withdrew.

On the first and second floors, all the windows and doors are opened, waiting for the site to volatilize naturally.

"Well, let's wait and go in again. Director Li looked at the warning tape, "Pull the warning tape out a little more, don't let people watch." ”

...

"Team Zhao, you take Xiao Wang and back up all the video materials in the vicinity first; Team Li, you take Xiao Bai upstairs to take a look and stabilize the owner of the house upstairs..."

This is a row of commercial streets, with underground garages below, some ordinary residential buildings above, and ground floor merchants.

The thief's way of entry was to rent the upstairs in advance, and then, this afternoon, he began to open the floor between the upstairs and the gold shop.

The building here is still relatively new, and the floor structure is reinforced concrete, which is very difficult to penetrate, but with hydrofluoric acid, reinforced concrete is not as good as plastic or wax.

Hydrofluoric acid and hydrogen cyanide in Sun's previous suicide case are completely two different things. Because it cannot be completely ionized in water, hydrofluoric acid does not belong to the strong acid series, but this does not mean that this thing is not fierce, in fact, it can be said to be very acidic except that it does not act so fast.

Because of this, this thing is also a controlled item, which ordinary people can't get, but because it is a controlled item, once it appears, it is generally not a good use. However, as a policeman, after Bai Song mentioned hydrofluoric acid, everyone else is not unfamiliar. Because this acid has other uses in many cases...

Downstairs, Director Ma listened to Hao Zhenyu's report and had a better understanding of the scene.

This kind of theft is unheard of, mainly because the movement is too big, does this thief really think he can run away?

Normal thieves are just picking locks, secretly picking doors, etc., how can they be so alarmed, monitored, and make such a big move.

But the people present, including the owner of the gold shop, were a little impressed by the thief's "hardcore operation", such a brain hole is really rare.

The thief first pried open the floor of the bedroom upstairs, then drew a circle on the cement floor, and then surrounded the plastic board, and sealed the surrounding of the plastic plate with a substance of unknown composition, and then poured hydrofluoric acid.

Hydrofluoric acid has a strong corrosive ability to silica and concrete, but the speed is not fast, this is a continuous process, and it needs to be cleaned continuously.

Since this corrosion is not directly downward, but diffuse, the further down it dissolves, the larger the hole becomes, and eventually it dissolves through.

This substance has a very special property, which is a weak acid.

Weak acid should have been learned in junior high school, that is, acetic acid, which is an acid that cannot be completely ionized in water. However, when the concentration exceeds 5 moles per liter, self-ionization occurs, and hydrofluoric acid is a very acidic acid, which naturally corrodes the steel in reinforced concrete.

This thing is poisonous, and high concentrations of hydrofluoric acid will naturally produce acid-containing fumes, which can cause devastating damage to the respiratory tract, and the lethal dose is only one or two grams. Therefore, the effect of gas masks on this can only be said to be average, even if the room is all left, but you should wear full-body protective clothing and oxygen ventilators.

The inorganic chemistry that Bai Song is learning now belongs to a very basic knowledge point.

The situation upstairs is that the bedroom does not dare to enter casually, one is afraid of damaging the scene, and the other is worried about the quality of the floor slab, so as not to have any accidents.

The owner of the house really cried miserably, who will pay for this situation? How can this house be repaired? It can only be blocked for a while.

The second floor was sealed off first, and the owner of the house was also taken to the station by someone from the police station to take the record.

Team Li and Bai Song went downstairs, went to Director Ma, and reported the situation on the second floor in detail.

Now there are no really good conditions for entry, everyone has heard of the power of hydrofluoric acid, Director Ma will not let people in anyway, he is a little afraid, if it were not for Hao Zhenyu's rich experience, requiring that he must wear protective gear and gas masks, there would have been a big problem at this time.

The damage of hydrofluoric acid to the human body is a chronic process, it actively reacts with calcium and magnesium ions, causing the organs that work on these two ions to gradually fail, usually after a few hours before the problem is discovered, and it is too late to find the problem.

Director Ma confirmed again and again, but he was still not at ease, and arranged for someone from the police station to take four on-site investigators to the hospital. Wang Huadong and Sun Jie both have a certain amount of bare skin, and they need to use calcium gluconate gel for protection in time, this thing is really fierce.

The scene is here, and it is better not to investigate it for the time being, than to allow his subordinates to have health or safety risks.

The last time he did a face sketch, Director Ma was reluctant to find someone outside the sub-bureau, but this time he was unambiguous and called the relevant departments of the city bureau directly.

After all, he was already the deputy director, and the phone call of the Ma detachment directly went to the command center of the city bureau and described the situation at the scene in detail. In addition, I have already reported it once on the radio, and this call is mainly for help.

When it comes to hazardous chemicals, the city is more powerful, and it's too normal for this kind of thing to be reported.

While waiting, Director Ma held a meeting at the scene.

According to what has been extracted from the scene and the evidence, the stolen jewelry is basically the same as described by the owner of the gold shop. There are six or seven jewelry cabinets in the store, half of which are silver and half are gold, and there are a few diamond rings and platinum jewelry scattered in each cabinet.

The thief's theft was very pointed, and he went straight to the cabinet where the bracelet was kept, and nothing else was touched.

The quality of this cabinet is not as good as imagined, that is, the reinforced iron cabinet, which can't withstand the crowbar at all, the thief seems to have been prepared, and went straight to the point, taking away the dozens of bracelets and sporadic diamond rings under the cabinet directly.

There is a safe in the store, and generally speaking, new goods or goods that are not placed on the surface, as well as things like gold bricks and gold ingots, have been placed in large safes worth hundreds of thousands of yuan. The clerk at this store does not have a safe key, so everything is kept in the locker every day.

The thief didn't touch the safe, nor did he touch the other cabinets, and for now, this cabinet is indeed the most valuable cabinet in the entire store. Because for the rest, even if you put 100 rings, it's about 400 grams.

I have to say that this is a successful act, and compared to many stupid thieves, the planning time should have been very long.

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