Several people didn't even bother to eat lunch and rushed to the internal parking lot of the Public Security Bureau.
At the end of the parking lot, there is a two-story evidence collection and identification center. Several people were led by the attendant through the small building and finally arrived at the small backyard.
"Ouch...woof!"
Just when I heard the footsteps, the mad dog brought back from the Mobei Hongdu shooting incident started barking again.
After not seeing each other for a few days, this mad dog seemed to be getting more and more angry. After seeing Xu Tiannan and others arriving, he jumped up and down like crazy in the cage, almost overturning the huge iron cage.
The duty officer said with a depressed look on his face: "Oh, Captain Wen... your criminal investigation detachment really brought back a treasure this time. Is this broken dog sick? It's been fed for so many days and it still doesn't seem like it recognizes me."
Every time he sees me, he wants to rush over and bite me."
While talking, the attendant scooped up a small bowl of dog food from the shelf nearby and poured it in through the gap in the iron cage.
"Woof!"
When the mad dog saw someone approaching, he yelled loudly, and then, as if declaring his territory, he turned his head and began to bite the cage in front of him, and the whole dog's body began to shake crazily.
Seeing this, Xu Tiannan suddenly said loudly: "Yes! That's the problem!"
"Ah? What's the problem?"
Wen Sibao asked puzzledly, but saw Xu Tiannan suddenly lying on the ground, and gradually moved his head closer to the iron cage, and the mad dog in front of him was suddenly stimulated, screaming for a while, and biting harder for a while.
Set up a cage.
"Woof woof woof woof woof woof! Click, click, click, click!"
"Boss, you are crazy..."
Just as Murong Shui was about to step forward to stop him, Xu Tiannan suddenly stood up and said, "Fourth Master, let me ask you, have your team members completed the investigation of all places in Xicheng District?"
Wen Sibao: "Well, except for the two locations in residential areas and commercial streets that do not need to be investigated, the rest of the places have basically been checked, but no results have been obtained yet."
Xu Tiannan explained: "That's because we used the wrong method before and focused our attention on this mad dog, but now I suddenly thought of something."
"What's up?"
Xu Tiannan said.
——"If we keep focusing on this mad dog, it will probably be difficult to find the place where it was raised before."
——"After all, even if you exclude the residential houses and commercial streets in Xicheng District, there are still many places that can provide a breeding environment."
——"But if we focus on the mad dog's cage, we will be able to accurately locate the location where the mad dog was."
Seeing that the other party was still puzzled, Xu Tiannan continued to explain: "If we can deduce the characteristics of the cage when the murderer raised mad dogs, you can directly ask the investigators to compare each house and go to Xicheng District to find those with the same characteristics.
This way, the scope of investigation can be greatly reduced!”
Upon hearing this, Wen Sibao's eyes suddenly widened and he asked hurriedly: "Really? If we can really find the cage where the murderer kept the mad dog, we can let Li Mengxue and his team go to the scene to inspect it.
Take the feces or soil samples there to see if there is canine coronavirus carried in this mad dog, and then you can directly locate the place where the murderer was raised!"
Xu Tiannan nodded, "That's what it means. This is exactly what Meng Qinghan said before."
Wen Sibao asked hurriedly: "Then what do you think the characteristics of the dog cage were when the murderer behind the scenes raised this mad dog?"
Xu Tiannan pointed to the iron cage in front of him and asked: "Then first take a look at the characteristics of this dog?"
When Wen Sibao took a closer look, the mad dog suddenly felt hostile again, barked loudly, and then bit the iron bars of the cage.
Wen Sibao: "Well... this dog seems to have a strong sense of territory and likes to bite the cage. Every time someone gets close, it looks like it is eager to bite off the iron fence and rush out."
Xu Tiannan explained.
——"Yes! This time we are going to take advantage of this and go to Xicheng District to find iron cages with the same characteristics."
——"Dog cages available on the market are usually not made of pure steel due to cost considerations, so most of them are made of iron products."
——"The processing of iron products is divided into pig iron and wrought iron. Pig iron contains high carbon content. Although it is hard, it is too brittle. Once it is subjected to pressure, impact, or in an environment with a large temperature difference, it will easily crack."
——"So the dog cages and iron fences sold on the market are all made of wrought iron. The characteristics of wrought iron are higher toughness and higher ductility, but it has one of the biggest advantages, that is, it is more durable than pig iron.
Soft and malleable.”
After explaining the above, Xu Tiannan asked Murong Shui to come closer, pointed to the iron cage fence that was being bitten by the mad dog, and asked: "You have good eyesight, come over and take a closer look, are there many bites on this iron fence?"
trace?"
Murong Shui was puzzled, but he still looked closer. Sure enough, he soon found several small marks that had been bitten by the mad dog on the bars of the iron cage. He hurriedly responded: "Yes! This mad dog has enough teeth."
It’s so sharp! It’s even chewed up the iron fence!”
Xu Tiannan said: "This is all because this dog cage is made of wrought iron, so it will leave these small bite marks on it. And based on this characteristic, we can let the investigators run to Xicheng District again to take a look.
Can you find an iron cage with the same characteristics?"
After finishing speaking, Xu Tiannan asked the attendant to lure the mad dog away with food, then took out a tape measure and measured the bite marks on the dog cage in front of him.
——"The bite mark density is within 3-5mm, and the bite mark position is between 19-27cm from the bottom of the cage."
——"That is to say, this dog is not only used to biting the iron cage in front of it, but also bites within this range after lowering its head."
——"Hurry up and investigate. Maybe the murderer will clean up the environment where the mad dog was raised after the mad dog is taken away, but the other party will never expect the features on this cage."
Wen Sibao nodded, and immediately called for a quick gathering of personnel to re-launch the investigation into Xicheng District. This time, everyone's focus was on finding pet cages with the same characteristics.
This chapter has been completed!