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

Technical tracking of "Lone Ranger" has also yielded no progress; the account seems to have appeared out of thin air, with no clues to follow.

Just when everyone was at a loss, the team members responsible for reviewing surveillance footage made a new discovery. While retrieving footage from a private surveillance camera near a gap in the northwest fence of the unfinished building in the northern suburbs (the camera belonged to a small nearby processing plant and had previously been overlooked), they discovered a suspicious figure. The footage showed that around 2:30 AM on the day of the incident, a man wearing a black coat, a black hat, and a mask entered the unfinished building area through the northwest gap in the fence, seemingly carrying something in his hand. About an hour later, around 3:30 AM, the man emerged from the same gap; his coat appeared to be covered in something, and his gait seemed heavier than when he entered.

After zooming in on the surveillance footage, the team members discovered that the man's height and build were almost identical to the stranger described by the neighbors, as well as the man seen arguing with Zheng Kaibin in the surveillance footage at the community entrance. More importantly, the man was wearing rubber-soled shoes, and the shoe size and pattern closely matched the size 42 horizontal striped rubber-soled shoe prints found at the scene!

"This man is the suspect!" Wang Shuai said confidently, looking at the surveillance footage. "Immediately process the footage to improve clarity, extract the man's gait characteristics, clothing details, and other information, and create a notice for assistance in the investigation, which will be circulated throughout the city! At the same time, expand the scope of the surveillance investigation to track the man's complete trajectory as he enters and leaves the unfinished building area!"

The technical department immediately processed the surveillance footage to improve its clarity. Although the man's face was obscured, his clothing characteristics were clearly visible: a black hooded jacket, a black mask, black pants, and size 42 striped rubber-soled shoes. The team tracked the man's movements using surveillance cameras and discovered that he arrived near the unfinished building on an unlicensed motorcycle. The motorcycle stopped on a small road about 500 meters from the gap in the construction fence on the northwest side. After the incident, the man rode the motorcycle towards the urban village in the northern suburbs, eventually disappearing at an intersection without surveillance cameras.

After the notice for assistance was issued, the Criminal Investigation Detachment received numerous tips from the public, but after verification, most were false alarms, and no one matching the suspect's description was found. However, one tip caught the team's attention. A resident of a village in the northern suburbs reported that the day after the incident, he saw a man wearing a black hooded jacket burning clothes near a garbage station in the village. He found it strange at the time but didn't think much of it.

Wang Shuai immediately led his team to the garbage station and conducted a thorough investigation of the surrounding area. In a corner of the garbage station, the team found a small number of fragments of clothing that had not been completely burned. The fragments were black in color and the material was similar to that of the jacket worn by the suspect in the surveillance footage. The team retrieved these clothing fragments and sent them to the technical department for testing.

The technical department's tests showed that the fiber composition of these clothing fragments perfectly matched the gray and black fibers extracted from the scene! This further confirmed that the man who burned the clothes was the suspect. The team conducted a thorough search of the urban village, collecting DNA samples from all individuals matching the suspect's characteristics for comparison, but still found no matches.

Twenty-five days after the incident, the investigation had made no substantial progress. Although the suspect's clothing, gait, and DNA characteristics had been identified, and some of his movements had been tracked, the suspect's strong counter-surveillance awareness—including covering his face, using an unlicensed motorcycle, and burning his clothing during the crime—made it difficult to advance the investigation further.

Wang Shuai convened another meeting with his team to re-examine all the clues in the case. "Currently, it seems there is some connection between the suspect and Zheng Kaibin, and the murder is likely caused by some kind of transaction or dispute," Wang Shuai analyzed. "The 'transaction' mentioned in the chat logs between Zheng Kaibin's anonymous social media account and 'Lone Ranger' is likely the key to the case. We must find out the specific details of this 'transaction' as soon as possible."

Zhang Kai said, "We can conduct a more in-depth technical analysis of Zheng Kaibin's computer to see if we can recover his deleted chat history and files, and perhaps find more information about the 'transaction'."

The technical department immediately conducted a comprehensive technical inspection and data recovery of Zheng Kaibin's computer. After two days of effort, the technicians successfully recovered some of the deleted chat logs from Zheng Kaibin's anonymous social media account. The recovered chat logs showed that Zheng Kaibin and "Lone Ranger" had been in contact for a month before the incident, discussing a "transaction concerning trade secrets." Zheng Kaibin sold "Lone Ranger" a "list of foreign trade clients" for 50,000 yuan. The agreed transaction location was an unfinished building in the northern suburbs, and the transaction time was 2:00 AM on the day of the incident.

"So that's how it is!" Wang Shuai suddenly realized, "Zheng Kaibin was killed by 'Lone Ranger' because he had a dispute with the buyer during a transaction involving an unfinished building while selling trade secrets!" This discovery finally pointed the way to solving the case.

Based on the recovered chat logs, the team immediately reviewed Zheng Kaibin's list of foreign trade clients and discovered that one list containing information on several important clients was missing. This list involved trade secrets from multiple companies and was of immense value. The team then launched an investigation into this client list, examining which of Zheng Kaibin's business partners might have suffered losses due to its leak, or who had a motive to obtain it.

During the investigation, the team discovered that Zhou Ming, a business manager at a large foreign trade company that Zheng Kaibin had previously worked with, was facing job loss due to the company losing several important clients and being held accountable. These lost clients were precisely those on Zheng Kaibin's missing client list. More importantly, Zhou Ming's height and build closely matched the suspect's description, and he owned a motorcycle with a license plate. However, on the day of the incident, his motorcycle was neither parked in the company parking lot nor at home; its whereabouts were unknown.

Wang Shuai immediately arranged for his team to investigate Zhou Ming. By reviewing Zhou Ming's call records, they discovered that he had made multiple calls to an unregistered temporary number before the incident. This temporary number belonged to the same operator and batch of numbers as the suspected deceased's disconnected phone number obtained from the Ankang Dental Clinic! (End of Chapter)