This is another homicide crime scene, the body has been carried away the day before, from the preliminary autopsy results, the deceased male, named Yan Jitian, 50 years old, is an associate professor in the Department of Physics of Zhonghu University of Technology, the scene of the crime is Yan Jitian's home.

The cause of death of the deceased was repeated blows to the face and back of the head with a blunt object, there was no sign of a fight in the room, and there was no sign of the door lock being picked, and it was initially inferred that an acquaintance committed the crime.

The deceased was a divorced person, and the children and ex-wife had emigrated and had only occasional contact over the years, so the deceased lived alone. I asked the neighbors around, and I didn't hear any quarrels or anything like that in the past two days, but the downstairs neighbors said that a few nights ago, they heard several sounds of heavy objects falling on the ground, which were particularly huge, like someone hitting the ground with a hammer;

When the technical department called for community monitoring, it was found that the night before the incident, all the cameras in his community failed, and all the electronic components of the monitoring host in the community security room were also burned by an unexplained electromagnetic attack, and all the data in the hard disk were also destroyed.

Of course, Li Xian brought Du Lin not to ask him to analyze the social relations of the deceased, but to have difficulties in determining the murder weapon, and he needed Du Lin's help to take a look.

Shui Guochang analyzed the shape of the murder weapon according to the bone crack of the deceased's skull. The murder weapon was supposed to be a blunt object with a round head, about three centimeters in diameter, but no similar objects were found at the scene.

Du Lin observed the situation at the scene of the crime, this is a very high-end decoration of the house, about 140 square meters, in this area of Zhonghu City, the house price is not low, at least 20,000 yuan per square meter, the house alone is close to 3 million, and then look at the luxury of this decoration, the whole house down, I am afraid that more than 4 million, even if it is a loan to buy a house, he is just an associate professor in a university, can he afford such an expensive house? Of course, maybe people have another side business.

It was found that there were a lot of broken glass near the location of the deceased, and there was a shelf on the bookcase next to it that was in a state of collapse, and it was estimated that there should have been an ornament on it before.

The on-site investigation believes that the murderer may have touched the bookcase in the process of entanglement with the deceased, causing a glass ornament placed on the bookcase to fall and shatter on the ground, so there are so many pieces of glass on the ground.

Du Lin found that the size of these glass fragments was very uniform, basically about 1~2 mm in diameter, and some were stained with blood, he picked up a piece of broken glass particles on the ground, "What kind of glass ornaments will be broken like this?"

Li Xian followed his example, and also picked up a piece of glass and held it in his hand, "Maybe it's some kind of special glass, such as explosion-proof glass or the kind of prop glass used in film and television dramas." ”

Du Lin shook his head and said, "No, the principle of explosion-proof glass is to sandwich a special film or extremely fine steel wire in the middle of the glass, so that when the glass is broken, small particles of about 0.5~1 cm will be formed, and it will be tightly attached to the film or steel wire, and will not splash around and hurt people, the glass in the film and television drama is not even glass, that thing is made of syrup and glycerin, do you taste this sweetness?"

Du Lin put the glass in his hand into Li Xian's mouth, Li Xian hurriedly dodged it, no need to taste it, and saw that this was a genuine glass, definitely not a sugar granule.

"And what is this?" asked Li Xian.

"I don't know," Du Lin put the glass particles in his hand and squeezed them hard, feeling its hardness, and found that the glass was still very hard, and it was not a problem to puncture the skin of his fingers, of course, it was the skin of ordinary people.

Li Xian also pinched, but was stabbed with blood, "I'm C, really pricked, why are you okay with pinching?"

"I'm thick-skinned. ”

Li Xian stood up, "Could it be that the murder weapon was really taken away by the murderer?"

"It should be, look here," Durin pointed to a pit on the floor, "this is about the location near the deceased's head, it may be that when the murderer hit the deceased's head with a murder weapon, the deceased turned his head and did not hit, and smashed to the ground, if it was an iron object, such as a round-headed hammer, there may be iron residues in this pit." ”

"We also found out that the people from the trace examination department have taken samples and will have results soon. ”

The two went around the deceased's house a few more times, and there was no blood reaction from the faucets and sewer outlets in the bathroom and kitchen, which means that the murderer probably had blood stains on it when he took away the murder weapon.

Li Xian said: "Generally speaking, it is unlikely that the murderer will go too far with the murder weapon, and he will definitely be in a hurry to dispose of it, and I have arranged for people to look for suspicious items in the nearby garbage bins and sewers." ”

"To be honest, I don't really believe that the murderer would take the murder weapon away, you see," Du Lin pointed to the location of the original body, "There is no dripping blood around the place where the body was found, which means that the murderer did not walk around with the murder weapon, and there are no traces of blood wiping on the deceased's clothes on the photo of the corpse, so how did the murderer transfer the murder weapon without letting the blood stains fall?"

"Maybe he wrapped a towel around the murder weapon and took it away?" Li Xian said.

"It's too troublesome, which means that in addition to the murder weapon, he also has to dispose of an extra towel wrapped in the murder weapon, which is equivalent to increasing the risk. Durin shook his head.

The phone rang, Li Xian picked up the phone, and after listening to a few words on the other side of the phone, he hung up the phone.

"The results of the trace examination at the pit came out, and there was no iron residue. ”

"Huh, not iron?"

"It seems that it is not, colleagues in the trace examination department said that it must take a lot of strength to leave such a deep pit, they have done experiments, and it takes at least about 800 N to smash out such a deep pit, and the arm strength of an adult male is about 400~600 Niu, that is, about 40~60 kilograms, which means that the murderer must be a strong male, so it seems that the suspicion of those female students can be ruled out. ”

"Not necessarily, it's not the female students themselves, it could be their boyfriends or something. ”

"That's right, then the focus of the investigation needs to be on their boyfriends. Another point, the trace examination department said, such a big force, even with an iron hammer, will leave a trace of iron residue in the pit, but the inspection results show that there is no iron at all, not only no iron, no residue of any metal element, only a little bit of silicon. ”

"Silicon?" a flash of inspiration flashed in Durin's mind, "Isn't silicon made of glass?"