There have also been significant discoveries in the field of forensic technical progress.

"Teacher, one of the seven skeletons has been identified."

The extraction of DNA information from bones has become more and more sophisticated with the development of technology.

Previously, bone DNA extraction could only be done from bone marrow, but later it was also possible to extract from bone.

Of course, this requires higher purification of bone genetic material, as well as higher requirements for the accuracy of instruments for genetic material analysis.

Zhang Yuanchao took the appraisal report and was a little surprised.

The bones of the identity of the person are not compared from the missing people.

Rather, it is the result of a DNA paternity test that has been done in the system, and the DNA of the bones and the father in the paternity test are homologous.

That is, they are brothers.

"Send the results to Li first, they can use them there."

In less than five minutes, the comparison results were sent to Li Donglin.

Arrests and interrogations on the front line proceeded at lightning speed.

At that time, all the people in charge of the bridge project did not know about these things.

Moreover, it is strange that there were three workers who were responsible for pouring the piers, but these three people were not found.

Now, one of them has been found.

Zhang Wanxiang, a native of Lingshui County, went out to work 30 years ago and has not been heard from since.

The family members have reported their disappearance, but they are working in QZ City, but they have not made any money, and they have not returned home for so many years.

The disappearance report of that year was naturally not resolved.

Unexpectedly, fifteen years ago, Zhang Wanxiang, who worked at the construction site of the Minghe Bridge, was finally poured into the pier he poured.

With the clues of the identity of the first person, the identity of the other skeletons was quickly determined.

The three workers who were in charge of pouring the piers suddenly resigned, and now they have not been found.

Now, it is estimated that they have all been watered in the piers.

Forensic laboratories.

Lu Chuan's experiment on the time of ossification of the bones also got the desired results.

Combined with the chicken leg experiment of pouring cement on the bridge pier, Lu Chuan speculated the time of the white ossification in the bridge pier.

Six of the corpses are not much different, and they are from the same period as the cement pouring period, but the corpses numbered Six are somewhat different.

Compared to other skeletons, this skeleton takes longer to ossify.

That's the problem.

According to the results of the forensic examination of the skeleton, the deceased was watered into the pier after a short death.

And based on the scars of the bones, the cause of death of the deceased was roughly determined.

However, the ossification time of the sixth skeleton seems to be shorter than that of the other skeletons.

In the dissection room, seven skeletons were lying on the ground side by side, and Lu Chuan observed again.

"Discovery?"

Zhang Yuanchao stood beside Lu Chuan and watched Lu Chuan carefully observe the seven corpses.

Lu Chuan nodded, pointing to the number five skeleton next to the sixth skeleton.

"Both skeletons were found in the second pier, and the external environment in which the bones were ossified was the same."

Zhang Yuanchao nodded, seven skeletons, the first four were found in the first pier, and the fifth, sixth, and seventh were all found in the second pier.

Under normal circumstances, under the same external conditions, the time of ossification of the corpse should be about the same, or even if there is a difference, it should not be too large.

At the very least, it is unlikely that after 15 years, it will be observed with the naked eye.

"In order to ensure that the quality of the bridge pier is qualified, it must be poured at one time."

What Zhang Yuanchao meant, Lu Chuan understood.

Just like the conclusion reached by several Zhang Yuanchao students when they did a superficial examination of the skeleton.

The bones were watered at the same time as they entered the piers, both alive and dead.

Of course, the same watering here is not instantaneous.

Instead, the concrete is poured before it solidifies, and in most cases the concrete used is pulled by the same truck.

At least it was produced in the same batch.

The reason for this is to ensure that the concrete height of the same pier is the same as possible.

Because, even if it is the same standard and mechanical control, there will be subtle differences in different batches of concrete.

Of course, there are very few things that can be done in reality, unless the supervision is very strict and the supervision is very powerful.

"This corpse has heavier marks of ossification than the others, or rather, it takes less time to ossify in the concrete seal."

Lu Chuan's brows furrowed: "This is a bit unreasonable."

Zhang Yuanchao nodded: "There are many reasons for this situation, such as the deceased took special medicines before his death, and there are special diseases in his body, etc., which may cause this situation."

"Well, to analyze it specifically, I suspect that it is drug abuse, and I need to take a test."

In many cases, it is difficult to make an accurate judgment and analysis of the identification and analysis of the skeleton.

In most cases, instrumentation is required.

The results of the verification surprised Lu Chuan and Zhang Yuanchao.

Inside the skeleton of corpse number six, there was a large amount of acrylic prefentanyl.

"Addicts?"

About 20 years ago, fentanyl-related drugs were included in the category of controlled drugs.

These drugs, known as neopsychoactive drugs at the time, have stimulant, hallucinogenic and anesthetic effects when used in excess.

Twenty years ago, any use of this drug needed to be documented, and used in limited quantities.

Zhang Yuanchao has been practicing medicine for so many years, and he has seen more than one addict.

Moreover, it can be detected in bones after fifteen years, which must be the result of long-term heavy use.

"When these substances are used in large quantities, the residual components have an erosive effect on the bones, so the color of bone number six is different from other bones."

"Report this situation to Li's side, this kind of drug has been controlled fifteen years ago, if it is used in large quantities, there should be a record, check it, and you may find the identity of the other party."

Of the seven skeletons, one has been identified and two are currently speculated to be the workers who poured the piers.

Someone has now been sent to collect the DNA information of his relatives and prepare for comparison.

But the identities of the other four corpses are not yet known.

After Li Donglin learned the news, he immediately arranged for the Qinzhou Criminal Investigation Detachment to investigate.

The heavy use of pre-fentanyl acrylic, if not a drug use, or a hospital prescription, and the use of this drug, is all using a red prescription.

In any hospital, the red prescription of drugs has a saying that you have to see people alive and see corpses when you die.

Even after more than ten years, you should be able to check the usage records.

Soon, the criminal police in charge of the investigation found the relevant drug use information in the drug management system of the First People's Hospital of QZ City.

From fifteen years ago to the present, there are only five patients who have used a lot of pre-fentanyl acrylic.

Two of them are now alive and receiving regular treatment.

Two others died of illness 10 years ago and 13 years ago.

There was only one person who entered the hospital for treatment eighteen years ago, but it was abruptly interrupted fifteen years ago.