The crackdown on organized crime began with the arrest of the mother-in-law.

Chapter 1316 Technical Appraisal Results

At 6 PM, as darkness fell, Xiao Wang led his team back to the Criminal Investigation Division to organize the interview records. "Team Leader Li, today we interviewed 12 households, 1 scavenger, and 10 construction workers. Only the scavenger, Lao Li, mentioned smelling an odor on the second floor of the building a month ago, and one resident mentioned seeing a white van parked nearby three months ago, but there were no further details. The CCTV footage was also unsatisfactory; there are few cameras in the area, and the resolution is low, so we didn't find any suspicious clues," Xiao Wang reported to Li Ming, his tone tinged with frustration. "Currently, we still cannot determine the deceased's identity or time of death, nor have we found any effective leads pointing to the suspect."

Li Ming looked at the visit log, his fingers tapping lightly on the table: "Although there were no major discoveries, the strange smell and the white van mentioned by the scavenger are potential clues. Tomorrow, arrange for someone to focus on investigating the whereabouts of that white van from three months ago, expanding the scope of the surveillance investigation to see if we can find its driving trajectory; at the same time, have the technical department conduct tests on the hair, blue cloth, and shovel collected at the scene as soon as possible, hoping to find a breakthrough from the physical evidence. In addition, continue to visit the shops and small stores around the shantytown to see if anyone has noticed any suspicious persons or vehicles, and don't overlook any details."

"Yes!" Xiao Wang nodded, regaining his spirits. "Tomorrow I will lead the team to continue the investigation and try to find more clues."

As night fell, the shantytown in the north of the city gradually quieted down, with only the police tape at the demolition site standing out conspicuously under the lights. Xiao Wang stood by the window of the Criminal Investigation Division, looking at the night outside, and silently made up his mind—even if the clues were few, he would persist in the investigation. He couldn't let the deceased remain buried under the rubble in vain; he had to find the truth and bring justice to the dead. Meanwhile, the lights in the technical department were still on, and the staff were working overtime to test the samples collected from the scene, hoping to find crucial clues from the smallest details that could bring a turning point in the case.

That evening at 7 p.m., the laboratory of the Criminal Investigation Detachment's Technical Section was brightly lit. Xiao Yang and Xiao Sun, dressed in white lab coats and sterile gloves, had neatly arranged physical evidence brought back from the demolition site of the shantytown in the north of the city on the lab table in front of them: three hairs sealed in an evidence bag, a piece of blue cloth, a rusty shovel, and two soil samples extracted from the shovel head and the area around the body.

"Let's start with hair and see if we can extract DNA. It might be directly linked to the deceased or suspect." Xiao Yang placed the first hair on the microscope stage, adjusted the focus, and the cross-section of the hair immediately appeared on the screen. "The hair cuticles of this hair are not very intact, and there is no hair follicle at the root, which means it was naturally shed or torn by external force. It will be difficult to extract nuclear DNA, so we can only try mitochondrial DNA."

Xiao Sun, who was preparing DNA extraction reagents, looked up and said, "It's indeed troublesome not having hair follicles. Mitochondrial DNA can only be traced back to maternal relatives. Even if the extraction is successful, we have to do a lot of comparisons in the database to find matching information, so it's difficult to get results in the short term. But let's try it first, just in case there's a surprise?"

The two worked together, with Xiao Yang handling microscopic observation and sample processing, and Xiao Sun handling reagent preparation and DNA extraction. After more than an hour of work, they failed to extract nuclear DNA from any of the three hairs, only managing to extract a trace amount of mitochondrial DNA from one hair. "We can only enter this mitochondrial DNA data into the database for now and compare it slowly. It's unrealistic to expect it to confirm the deceased's identity in the short term," Xiao Yang said, taking off his gloves and rubbing his throbbing temples, his tone tinged with disappointment.

Next came the identification of the blue fabric fragment. Xiao Yang placed the fabric fragment under a Fourier transform infrared spectrometer, and the instrument quickly generated a composition analysis report for the fabric. "The composition is polyester fiber, which is what we commonly call polyester. This material is very common and widely used in work clothes, sportswear, curtains, and other items. Without special brand or place of origin markings, it is difficult to narrow down the scope of the investigation."

Xiao Sun picked up a piece of fabric and examined it under the light: "Look at the fabric's texture. It's a plain weave, and there are obvious tear marks on the edges. The fibers at the tear are worn, indicating that it's not a recent tear; it's been there for at least some time. Also, there are a few dark red stains on the fabric. Let's test if it's blood."

He scraped off a small amount of stain from the fabric fragment, added luminol reagent, and under ultraviolet light, the stain did not show the typical blue fluorescence. "It's not blood; it's probably rust, dirt, or other contaminants," Xiao Sun recorded the test results. "This fabric is too ordinary. Apart from knowing it's made of polyester and has a plain weave, there's no information that points to a specific person or scene. It's basically of no investigative value."

The two then focused on the shovel and soil samples. Xiao Yang wiped the shovel head with a cotton swab, took a sample, and conducted a metal composition analysis. The results showed that the shovel head was mainly composed of cast iron, and the rust on the surface was composed of iron oxide, consistent with the composition of ordinary civilian shovels. There were no special alloys or processing marks, making it impossible to trace the purchaser or user through material traceability.

"Let's examine the soil samples again. Compare the soil on the shovel head with the soil around the body to see if they come from the same area." Xiao Sun weighed the two soil samples on an electronic balance, then added distilled water and stirred, observing the settling speed and stratification of the soil particles. "From the settling stratification, the proportions of sand, silt, and clay particles in the two soil samples are basically the same, both belonging to loam. Moreover, the organic matter content and pH value in the soil are also the same, indicating that the soil on the shovel head did indeed come from the area around the body. This proves that this shovel is most likely the tool used to bury the body."

Xiao Yang added, "But just knowing that isn't enough. The shovel is severely rusted, there are no fingerprints on the handle, and no engravings or markings, so we can't determine who its owner is. Let's check the vendors in the city who have sold this model of shovel in the last three years and see if we can find any purchase records?"

Xiao Sun shook his head, opened his computer and pulled up the relevant data: "This type of cast iron flat-bladed shovel is the most common model on the market. There are at least 50 hardware stores in the city selling it, and most of them are cash transactions without buyer registration, so it is impossible to trace its source. Unless we can find special wear marks on the shovel that match the usage habits of a specific user, but that is too difficult and hard to achieve in the short term."

The two then assessed the wear and tear on the shovel handle.