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

Surveillance footage shows Qin Kailai dragging a large black suitcase into Nanhu Square at 4:27 AM. The size and shape of the suitcase perfectly matched the black leather suitcase found at the scene. Qin Kailai then walked along the western fitness equipment area towards the central lake, disappearing into a blind spot of the surveillance cameras near the waterfront platform on the north side of the central lake. Approximately 20 minutes later, Qin Kailai left Nanhu Square alone and drove away from the parking lot. This movement perfectly matches the time and route of the body disposal previously determined by Xiao Wang's team!

"The evidence is conclusive. Apply for an arrest warrant for Qin Kailai immediately!" After comprehensive analysis, Xiao Wang and Xiao Zhou unanimously concluded that Qin Kailai was a prime suspect and that there was evidence proving he had disposed of the body. Upon receiving the report, Li Ming immediately approved the arrest warrant application and ordered Xiao Wang and Xiao Zhou to lead their team to carry out the arrest operation.

At 3 PM that afternoon, Xiao Wang and Xiao Zhou led eight detectives to Qin Kailai's residence to make the arrest. Upon arriving at the residential complex, the team first set up a perimeter to prevent Qin Kailai from escaping. Then, Xiao Wang led the team to Qin Kailai's apartment building and knocked on the door, but there was no answer. "Qin Kailai, we are police officers from the Municipal Criminal Investigation Detachment. We need to ask you something. Please open the door!" Xiao Wang identified himself and knocked again. There was still no response from inside. The team learned from the property management that Qin Kailai had gone out once that morning, returning to his residence around 10 AM, and hadn't left since.

"Prepare to break down the door!" Xiao Wang decisively gave the order. The team members immediately used breaching tools and successfully opened the door. After entering the room, the team members quickly searched the room and found Qin Kailai hiding in the bedroom closet, looking panicked. "Don't move! Police!" The team members immediately stepped forward, subdued Qin Kailai, and handcuffed him. Qin Kailai tried to resist, but was quickly subdued by the team members.

During the search of Qin Kailai's residence, the team discovered several important pieces of evidence: a black down jacket with a small amount of dark red stains, which, according to preliminary testing, appeared to be bloodstains; a kitchen knife of the same model as the stainless steel kitchen knife recovered from the scene, with slight wear marks on the blade; an empty mineral water bottle, matching the brand of mineral water Qin Kailai had purchased, as reported by the convenience store owner; in addition, the team found several gambling IOUs in the room, totaling more than 5 yuan, as well as a notebook recording loan information, which detailed financial transactions with Zhang Baocang, including loan dates, amounts, and repayment details, with the last loan of 8 yuan marked as "unpaid."

Subsequently, Qin Kailai was escorted back to the Municipal Criminal Investigation Detachment to await interrogation. During the transport, Qin Kailai kept his head down, remained silent, and appeared grave. Upon returning to the Criminal Investigation Detachment, the interrogation immediately commenced. Experienced investigators Lao Chen and Xiao Li were in charge of the interrogation, while Xiao Wang and Xiao Zhou supervised the entire process in the monitoring room.

The interrogation room was brightly lit and the atmosphere was serious. Qin Kailai sat in the interrogation chair, his hands cuffed to the armrests. Old Chen first showed Qin Kailai the arrest warrant, then said, "Qin Kailai, you should know very well why we arrested you. Now, I hope you can truthfully confess your crimes and strive for leniency." Qin Kailai raised his head, his eyes darting around, and remained silent.

"What is your relationship with Zhang Baocang? What's the story behind your financial dealings?" Old Chen began to ask. Qin Kailai licked his lips and slowly said, "Zhang Baocang and I used to be colleagues, and we had a pretty good relationship. We just lent each other money for short-term needs, nothing more." "Lending each other money? Then why did Zhang Baocang transfer 8 yuan more to you than you transferred to her? What happened to that 8 yuan?" Old Chen pressed. Qin Kailai's body trembled slightly as he said, "That 8 yuan was a loan from him. I originally intended to pay it back, but I've been short of money lately and haven't been able to."

"Tight on cash? Is it because you lost money gambling?" Old Chen directly exposed Qin Kailai's current situation, and placed the gambling IOUs that had been found in front of him. "These IOUs are all yours, right? You owed a lot of money because of gambling, borrowed money from Zhang Baocang but couldn't repay it, and he kept pressing you for it, so you had the idea of ​​killing him, right?" When Qin Kailai saw the IOUs, his face turned pale instantly, and his hands began to tremble.

“We have solid evidence,” Xiao Li added. “At 21:30 p.m. the night before the incident, you called Zhang Baocang, wasn’t that to arrange a meeting to discuss repaying the money? Around 22 p.m., you drove your black Volkswagen Magotan away from home to the vicinity of Nanhu Square, wasn’t that to meet Zhang Baocang? At 4:27 a.m., you dragged a black suitcase into Nanhu Square and threw the suitcase into the central lake. That suitcase contained Zhang Baocang’s body, didn’t it?”

Qin Kailai's mental defenses gradually crumbled. He lowered his head, his shoulders trembling uncontrollably. After a few minutes, Qin Kailai raised his head, tears streaming down his face, and slowly said, "I did it... I killed Zhang Baocang..."

Subsequently, Qin Kailai recounted the entire process of murdering Zhang Baocang. It turned out that Qin Kailai was a long-term gambling addict who had accumulated a large gambling debt. To repay this debt, he repeatedly borrowed money from Zhang Baocang, who, out of consideration for their past relationship, always agreed. Initially, Qin Kailai was able to repay on time, but as the gambling debts piled up, he gradually became unable to pay. In the past six months, Zhang Baocang, facing significant financial pressure due to bidding for projects, began frequently pressing Qin Kailai for repayment. Qin Kailai always made various excuses to avoid it, leading to conflict between the two.

The night before the incident, Zhang Baocang called Qin Kailai again, demanding the repayment of the 8 yuan debt. He threatened that if Qin Kailai didn't pay, he would tell his family and former colleagues about his gambling debts and take legal action against him. Fearing exposure and damage to his reputation, and also unable to repay the debt, Qin Kailai conceived the idea of ​​killing Zhang Baocang. He feigned agreement on the phone, arranging to meet Zhang Baocang that evening near Nanhu Square to discuss the repayment. Zhang Baocang, unsuspecting, agreed to meet.

Around 22 PM that evening, Qin Kailai drove a black Volkswagen Magotan to the agreed-upon location near Nanhu Square. Upon Zhang Baocang's arrival, the two argued again about repaying the money. Zhang Baocang became agitated and threatened to sue Qin Kailai immediately. Seeing this, Qin Kailai harbored malicious intent. Taking advantage of Zhang Baocang's inattention, he took a pre-prepared soft towel from the car and covered Zhang Baocang's mouth and nose. Zhang Baocang struggled desperately, sustaining superficial scratches on his left forearm from Qin Kailai, but ultimately died of asphyxiation.