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

During the on-site investigation, a "size 42 grid-patterned footprint" was found on the ground on the east side of the elevator lobby, with an estimated weight of 65-70 kg, which matches Tang Hu's weight of 70 kg. A "size 43 Anta brand rubber-soled shoe print" was found on the outside of the door, with an estimated weight of 75-80 kg, which matches Chen Kaifeng's weight of 78 kg. There were "strip-shaped scratches and circular impact marks" on the wall. The cause of these marks was perfectly explained in Chen Kaifeng's account.

“He resisted fiercely, shouting ‘If you dare kill me, I won’t let you get away with it,’ threatening revenge. I was terrified, afraid his shouts would attract others, and afraid I wouldn’t be able to control him, so I stabbed him even more frantically.” Chen Kaifeng’s voice trailed off, trembling slightly. “I remember stabbing him four or five times in total, all in his chest. The last stab went in particularly deep, and his body went limp immediately. He stopped struggling, but his eyes were fixed on me, as if he was very unwilling to accept defeat.”

The forensic autopsy report showed that Tang Hu had a wound 2 cm medial to the midclavicular line at the fifth intercostal space on his left chest, approximately 3.5 cm long and 1.2 cm wide, with irregular edges and obvious signs of tissue bruising; one angle was blunt and the other sharp. The wound cavity was approximately 8 cm deep, and a probe could touch the pleural tissue. There was also a tear in the anterior wall of the left ventricle, corresponding perfectly to the superficial wound, approximately 2.8 cm x 1 cm in size, with irregular edges and signs of myocardial tissue bruising. He ultimately died from "left ventricular rupture caused by a single-edged sharp instrument, resulting in hemorrhagic shock." Chen Kaifeng's description of the stabbing location, number of stabs, and force perfectly matched the characteristics of the fatal wound identified by the forensic examination.

"After he fell to the ground, he bled a lot, and a large pool of blood quickly formed on the ground." Chen Kaifeng's gaze fell on the dark red mark on the ground, his eyes filled with fear. "I was so scared that I was shaking all over. I stood there stunned for several minutes before I realized that I had killed someone. I quickly looked around to see if I had left any traces. I saw my cigarette butts on the ground, as well as the folding knife that had fallen and his cell phone, so I wanted to take all of these things with me."

“I picked up the folding knife and found the blade was covered in blood, so I wiped it with the corner of my clothes, but it wasn’t clean. I then picked up his phone to see if there were any messages, in case he told someone he wanted to see me, that would be troublesome. But the phone screen was broken and it couldn’t be turned on, so I threw the phone on the ground,” Chen Kaifeng said. “I saw a few drops of blood on the ground below the door, which must have been blood from when I was fighting. I even tried to wipe it off with my foot, but it didn’t come off. I didn’t expect you to find it.” During the on-site investigation, “several dark red drops of blood were found on the ground below the door, about 1.2 meters high,” which matched the height of Tang Hu’s left chest wound, which was about 1.4 meters above the ground, and was also consistent with Chen Kaifeng’s account of “blood dripping on the ground.”

Zhang Hui pressed further, "Did you notice anything unusual about Tang Hu's body at the time? Several coins, a supermarket receipt, and some fiber samples were also found at the scene." Chen Kaifeng recalled, "There were a few coins in his pants pocket that fell to the ground, but I ignored them. There was also a crumpled supermarket receipt, the writing was all blurred, probably left over from his shopping trips. As for the fibers, it's possible that during our struggle, fibers from his clothes fell onto me, or vice versa. I was wearing a black polyester work jacket at the time, so some fibers might have come off." During the on-site investigation, "a small amount of black polyester fiber" was found in the deceased's hair, which was different from the composition of the deceased's cotton clothing. Later testing confirmed that the fiber composition matched that of Chen Kaifeng's work jacket, confirming this detail.

“After I finished packing my things, I rushed to the door. When I got there, I looked back and saw him lying in a pool of blood, motionless. I was terrified, so I pushed open the door and ran out.” Chen Kaifeng’s voice was choked with sobs. “I ran down the stairs, afraid to take the elevator for fear of being caught on camera. When I got to the back door, I saw no one, so I quickly went into that alley. In the alley, I took out the folding knife and threw it in a trash can by the roadside? No, not a trash can, but the river. I remembered later that when I ran home, I passed a river and threw the folding knife in, thinking that way you wouldn’t find it.”

“I even burned the elevator card I took from my girlfriend with a lighter on my way home, and then threw the ashes into the sewer. I thought I had done everything perfectly, but I didn’t expect you to still find me.” Chen Kaifeng lowered his head, his voice choked with sobs. “I was wrong. I shouldn’t have killed someone over such a trivial matter. I’m sorry to Tang Hu and his parents.”

Zhang Hui listened attentively to Chen Kaifeng's account, every detail matching the crime scene investigation report and forensic autopsy report perfectly: from the characteristics of the folding knife used in the crime and the origin of the cigarette butt, to the fingerprints on the doorknob, the footprints and bloodstains on the floor, to the shape of Tang Hu's wounds, the formation of the resistance wounds, and the physical evidence left at the scene such as the mobile phone, coins, and fibers—there was no contradiction whatsoever. The technical staff reviewed the evidence on-site, reconstructing the struggle scene based on Chen Kaifeng's description of the angle and force of the stabbing, which perfectly matched the scratches on the wall and the pattern of the bloodstains on the floor.

As Chen Kaifeng was escorted away from the Chuangtian Building, the light rain had stopped. Sunlight streamed through the clouds, illuminating every corner of the building. Chen Kaifeng's confession, along with the fingerprints, DNA, footprints, murder weapon, and other irrefutable evidence collected at the scene, formed a complete chain of evidence, definitively confirming his crime. Thus, all the doubts surrounding the murder in the elevator lobbies on the roof of the Chuangtian Building were resolved, and the truth was revealed.

Back at the Criminal Investigation Division, the investigators immediately reviewed the physical evidence at the scene based on Chen Kaifeng's latest confession, further refining the case materials. The technical department re-examined the bloodstains on the folding knife blade, confirming a complete match with Tang Hu's DNA; the forensic department also supplemented the autopsy report based on Chen Kaifeng's account of the crime, clarifying the cause of each injury. All the evidence pointed to the same conclusion: Chen Kaifeng was the murderer of Tang Hu.

The murder case in the elevator room on the roof of Chuangtian Building has been successfully solved, and the suspect, Chen Kaifeng, has been arrested on suspicion of intentional homicide.

In the Criminal Investigation Division's office building, Lu Chuan looked at the complete case report and finally breathed a sigh of relief. "The solving of this case wouldn't have been possible without the hard work of all the investigators, and also with the strong support of the technical department and the forensic department." (End of Chapter)