Chapter 876: Suspect

There are many ways to identify circuit boards as identical, the simplest being to check the serial number and manufacturer's mark.

Regarding this point, after Huawei released its new CPU, many self-media outlets adopted this line of thinking. However, when the manufacturer or assembler deliberately conceals, etches away, or destroys the serial number and mark, or when they are missing due to explosions, fires, or other reasons, this trick has very limited utility.

Compared to the scheme of checking serial numbers and manufacturer marks, a slightly more complex method is to scan the circuit board's features or simply use image recognition technology for identification. This technology sounds particularly impressive, but in reality, it is quite unreliable when used. It is basically only useful inside the factory; once it leaves the factory, for a field like criminal investigation, a database issue alone can drive people to despair.

In the real world, there are many ways to identify traces and confirm identity; what truly hinders technological progress is actually database technology.

This includes the identification of footprints, shoe prints, palm prints, firearms, DNA, mitochondrial DNA, tire tracks, and so on, all of which face database problems.

Software is easy to make, but the data in the database really has to be entered one by one by police officers.

Over these years, only the fingerprint and DNA database entries have had some guarantee; other types of databases are basically in a state of "fencing off land for self-amusement," and they are definitely not easy to use.

Therefore, Jiang Yuan has used the technology of scanning circuit board features, and it is certain that it is useless.

In the end, Jiang Yuan still went back to arranging and combining components one by one. To use a more professional term, he observed the arrangement of specific components and connectors.

Circuit boards of the same model can have similar components and connectors, but for circuit boards produced by different manufacturers, the positions and layouts of different components still differ.

Additionally, it is easy to imagine that circuit boards produced by different manufacturers must also differ in the components they procure. And many components have their own markings, which cannot necessarily be wiped off.

The circuit board retrieved by the investigation team was already in a tattered state, so in the end, they could only determine the circuit board's model through the components themselves and their arrangement—first, they had to determine the circuit board's manufacturer. For most trace examiners, after completing this step, the work is roughly finished.

In most cases, the police can directly find the manufacturer and have the manufacturer's technical personnel determine the model of the wreckage. The method is the same, only the manufacturer's diagrams are more complete, and the personnel are more familiar with their own circuit boards.

Jiang Yuan was much the same; he only confirmed the manufacturer, then directly sent people over, found the same model on the manufacturer's computer on-site, and checked the manufacturer's sales records on-site.

Next, police officers flew to several distributors to extract and investigate further sales records.

Three days later.

At 3:30 AM, the ringing of a telephone woke Zhang Zhang Dinghui from his dream.

Zhang Zhang Dinghui sat up, his mind a blank.

The person beside him also turned over to check the time and said helplessly, "Are there so many things happening lately?"

"As long as it's not bad news." Zhang Zhang Dinghui shook his head and answered the phone: "I am Zhang Zhang Dinghui..."

"... We have determined the suspect's location." On the other end of the phone was the Municipal Bureau Chief, Deng Deng Jiabin.

Zhang Zhang Dinghui instantly became clear-headed: "You determined the location directly?"

He had gone to conduct research again yesterday, which was essentially acting as a supervisor; at that time, they were still under investigation, and there was absolutely no news of the suspect.

"Yes." Chief Deng Deng Jiabin responded, saying: "When the suspect traded to buy the circuit board, he used cash, but the shopkeeper's cash register had a time record. We found an intersection with a facial recognition camera where the suspect walked that day, and then had the shopkeeper confirm the suspect's identity."

Zhang Zhang Dinghui was actually quite familiar with these investigative methods. Hearing this, he let out an "um," his expression becoming even more serious, and asked: "What is the suspect's identity? How does he know the relevant technology?"

"The suspect, Ji Guo Haitao, is a farmer by background, currently 68 years old. He likely learned the technology for making explosives during militia training back in the day. Additionally, he has records of using the external internet, so he should have also learned some relevant technology." Deng Deng Jiabin answered very directly, stating the main content first, then adding: "This Ji Guo Haitao worked as a construction worker and also set off explosives in mines. Later, he led an engineering team himself. This time, the motive for the crime is very likely financial gain."

Zhang Zhang Dinghui let out a breath. If the suspect was after money, his anti-social attributes shouldn't be that heavy. What he feared most was the other party causing explosions everywhere for no reason, and that was exactly what he had been most worried about these past few days.

Deng Deng Jiabin knew the leader's thoughts well and continued: "We initially judge the deceased wearing the explosive vest to be Ji Guo Haitao's accomplice. Based on the description of witnesses at the scene, the two entered the finance office at the time, likely intending to use the explosive vest to commit robbery, but we currently have no way of knowing if they got the money or why the explosive vest exploded."

Zhang Zhang Dinghui let out another "um." A 68-year-old criminal suspect, even if in good health, would find it very difficult to rob a gambling den alone, and controlling another person wouldn't be easy either; an accomplice is indeed a more reasonable guess.

"Does he still have explosives in his hands?" Zhang Zhang Dinghui asked.

Deng Deng Jiabin: "In this regard, we are similar to our previous speculation. He should still have some. However, Ji Guo Haitao has not shown a tendency to make his own explosives; he mainly obtains materials through certain channels. Considering it from this angle, the explosives in his hands shouldn't be too many. Additionally, Ji Guo Haitao's economic conditions are also quite average; the explosives he used this time might even be leftovers accumulated from before."

Zhang Zhang Dinghui knew Deng Deng Jiabin was trying to put his mind at ease, but his mood did indeed relax a little. Looking at his wife sleeping restlessly beside him, Zhang Zhang Dinghui got up, took the phone, and while walking out, asked in a deep voice: "How do you plan to arrest the suspect? What is the situation at the scene?"

"The house Ji Guo Haitao rents is in the Anyue Bay residential area in the suburbs. It is a 28-story high-rise residential building with a tower structure and small units. There are many neighbors above, below, to the left, and to the right. There are 6 households on the same floor, all fully occupied. One of them is even rented by several people. There should be more than 20 people on a single floor." Deng Deng Jiabin only mentioned the neighbors on the same floor, not even the ones upstairs, which made Zhang Zhang Dinghui feel a thick sense of crisis.

"You cannot arrest him inside the residence." Zhang Zhang Dinghui said decisively: "Either lure him out to capture him... or see if you have any other plans."

Zhang Zhang Dinghui could already be considered quite enlightened; he didn't directly give a direction for his subordinates to follow. Even so, he had unequivocally vetoed the path of arresting him inside the residence.

Deng Deng Jiabin had also anticipated this point. Although, at this point in time, secretly sending people to sneak into the suspect's residence to arrest him was also a plan, the danger of this plan was also beyond doubt.

Even with the addition of various advanced instruments, such as thermal imagers, night vision goggles, and other equipment, you can't be sure how the suspect has placed and handled the explosives.

In case this person has a bit of persecution mania—it can't even be called mania now—and sets up some strange switches or mechanisms for the explosives, or even makes a booby trap on the door, the problem would be huge.

However, luring him out probably wouldn't be that easy either.

Deng Deng Jiabin didn't dare to guarantee anything, only saying: "I will go to the scene to command now and clearly convey your instructions!" ===== CHAPTER 877 =====