Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

Rinsing the blood agent with clean water can only clean the platelets, but cannot completely clean the DNA or protein substances in the blood.

To put it simply, rinsing the blood with water can only wash away the color. On the surface, it looks like there is no blood, but in fact some substances contained in the blood will still remain on the carrier.

To thoroughly clean away blood stains, you need to use some special cleaning substances.

This special cleaning agent is not a single cleaning agent, but a mixed cleaning agent.

In most cases, ordinary laundry detergent plus protease, mixed with some water, can clean away traces of blood more thoroughly.

The reason why protease is added is because the blood contains a large amount of protein material. It is because of the existence of this protein material that the DNA information in the blood can be detected.

The use of decomposing proteases can effectively decompose protein substances in the blood.

As for using laundry detergent, it can dissolve grease, which can make the damaged protein substances dissolve in water and then be washed away.

Of course, the specific protease content and the ratio between the amount of laundry detergent and the amount of water have more stringent requirements, so that the remaining traces of blood can be thoroughly washed away.

It is impossible for ordinary people to master it.

The murderer who killed Zhang Xiaotian's four people obviously did not have such a reserve of skills. He just used water to roughly deal with the blood stains.

Of the two pillows on the bed, the pillow cover on one of them disappeared. It is possible that the pillow cover was used by the other party to wipe the blood stains.

He should have been taken away by the other party afterwards.

In addition, Lu Chuan also found some bloody footprints at the scene.

"Is the murderer a woman?"

The coagulated blood did not contain the footprints of the two murdered men, as they had been fatally struck by a single blow, but there were the footprints of the two murdered women.

It is also easier to identify. The two murdered women did not wear socks or shoes, and the footprints left behind were barefoot footprints.

Based on the circumstances discovered so far, it can be roughly analyzed that the murderer entered the room while the four people were sleeping, and immediately attacked the two men, directly cutting their carotid arteries and killing them with one knife.

The two women were then awakened, possibly by the killer, and a struggle ensued.

During the fight, the murderer stabbed the two female victims with a sharp knife.

Among the footprints left in the pool of blood on the ground, in addition to the barefoot footprints, there is also a set of footprints that should be the murderer's footprints. They are quite special. The forefoot and back heels are the footprints left by high heels.

That's why Yang Sen said the other party was a woman.

However, the physical characteristics of the murderer that Lu Chuan gave based on the footprints were like this.

"With size 43 high heels, the murderer is 1 meters tall and weighs about 78 kilograms."

If the murderer is indeed a woman, then the murderer is indeed taller. This height is relatively rare among women.

Of course, it is not ruled out that the murderer is a man and deliberately wore high heels to hide his true footprints.

The next work is more detailed, collecting dander, hair, blood samples and other information at the scene.

Some blood and dander tissue were also found in the fingernails of the two female victims.

It is likely that during the struggle between the two parties, the two female victims scratched the murderer's skin.

"Killing with passion?"

Although the scene looked bloody, there were actually quite a few flaws left by the murderer, whether it was blood stains wiped with clean water or footprints in a pool of blood, or blood stains and skin flakes found in the fingernails of the two female victims.

Any clue can directly identify the suspect.Therefore, Yang Sen felt that the other party committed the murder out of passion. Otherwise, if it was a plot to kill, he would not have left so many obvious clues as long as he searched for more information on the Internet or watched a few movies.

"The probability of killing in passion may be higher, but it does not rule out that the other party has some plans. After all, judging from the time of the killing, the other party came to kill in the middle of the night."

"The four victims were all asleep at the time. The other party should have known the four victims in advance, or at least the homeowner, because at that time, it was impossible for them to have a direct conflict."

Of course, Lu Chuan said this, but he actually thought that the other party was a passionate murderer.

He just killed people on the spur of the moment without any planning.

The two of them were analyzing the case in a narrow room while collecting physical evidence for the investigation.

This busy work lasted almost three or four hours.

After the two came out, they handed over to the forensic doctor before Wang Changjiang and Shen Yan went in.

"How about it?"

Qin Yong looked at Lu Chuan and asked about the current survey situation.

"A lot of clues have been found. Based on the footprints left by the murderer, preliminary analysis shows that the murderer is 1 meters tall and weighs about 78 kilograms."

"The shoe prints left by the murderer were high-heeled shoes, but the size of the high-heeled shoes was very large, a full size 43. I am more inclined to think that it was a male murderer who deliberately wore high-heeled shoes to commit the crime."

"The maximum height error field is no more than two centimeters, and the weight is probably no more than five kilograms."

"Captain Qin, it should be him, will he be arrested or not?"

Zhang Hui, standing next to Qin Yong, looked excited when he heard Lu Chuan's survey results.

Judging from the results of the peripheral investigation, Wang Junshan, who once lived with Zhang Xiaotian, is suspected of committing a major crime.

The personal information about Wang Junshan found by the detachment was also passed on. The other party's height and weight were relatively consistent with Lu Chuan's current survey results.

"have goal?"

Lu Chuan knew as soon as he heard that Zhang Hui's visit and investigation had already targeted a person.

Zhang Hui nodded: "Zhang Xiaotian is gay, and the target suspect is likely to be his partner who once lived with him."

"Lu Chuan, what else have you discovered here?"

"In addition to the footprints, the murderer probably shed his own blood at the scene. We have collected some samples and tried to do some identification and analysis of DNA information. We also found some blood stains in the fingernails of the two female victims. and dander, possibly left by the murderer.”

"Great, you guys will get the results as soon as possible. Zhang Hui, you guys will arrest people first!"

"On Sun Jun's side, the surrounding surveillance cameras will be used to investigate and see if they can find a suspect with a similar body shape to the one given by Lu Chuan."

Although the surveillance of the building at the scene of the crime has been damaged, the surveillance of the surrounding roads is good. The other party cannot appear out of thin air. There is relatively little traffic in the middle of the night, so it is very possible to find clues about the other party.

In this way, through interviews and investigations, the target suspect and the evidence from Lu Chuan have been discovered, and coupled with surveillance, the case can be confirmed.

While the forensic doctor was doing the examination, the investigator had already driven back to the criminal investigation detachment.

It takes about one day to complete the DNA identification analysis.

Zhang Hui found Wang Junshan in another rental house two hours later. (End of chapter)