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

Xiao Lin rubbed his red, swollen eyes and smiled, tears still clinging to the corners of his eyes: "Over a thousand! We finally found them. My eyes are almost blind from looking." Li Bing lit his first cigarette of the day, the smoke dissipating in the sunlight. He took a deep drag, the dizziness from the nicotine making him sway: "Don't be too happy yet. Li Qiang, who owes him shipping fees, is a prime suspect. We need to immediately investigate his whereabouts on the night of September 10th."

The computer screen in the analysis room was still lit, hundreds of excluded names lying silently in the gray list, like countless fates brushing past each other. Zhang Hui gazed at the gradually brightening sky outside the window, the distant tower cranes outlining their black silhouettes in the morning light. Zhang Guojun's ID photo was still smiling on the screen, wearing his blue Lalamove uniform, his left breast pocket bulging, as if silently telling the story of that night of September 10th, how an ordinary Lalamove driver walked towards that cold water tank on his delivery route. Xiao Lin yawned and stood up, the chair legs scraping against the floor. He stretched, his bones cracking: "Anyway, at least we recognized the person, so it wasn't a wasted night."

Zhang Hui picked up the DNA report, his fingertips lightly tracing the name "Zhang Guojun," the rough texture of the paper seeping through his skin. He knew this was just the beginning. Li Qiang's shipping dispute, the recipient of Zhang Guojun's last order, the delivery slip lost from the pocket of his blue work uniform… countless mysteries awaited unraveling, but at least, this soul hidden in the water tank finally had a name. Sparrows hopped and chirped on the branches outside the window, their calls piercing the glass, as if cheering for this belated confirmation.

The blinds in the Criminal Investigation Division's conference room were just slightly ajar, letting in a slant of morning light that cast interplay of light and shadow on the long conference table. Lu Chuan slammed his enamel mug down on the table, the tea stalks swirling in the murky tea with a loud clatter that startled Xiao Lin, who was sitting opposite him, into straightening up. The quartz clock on the wall pointed to exactly eight in the morning, the ticking of the second hand particularly clear in the silent room, like a countdown to the analysis meeting.

"Everyone's here, let's begin." Lu Chuan tapped his fingers lightly on the table, his gaze sweeping over everyone present—Yang Lin's bruises were worse than yesterday, Zhang Kai's white coat cuffs had traces of iodine, Zhang Hui's cigarette pack was half empty, and Wang Shuai's notebook was covered with sticky notes of surveillance screenshots. He pushed Zhang Guojun's ID photo to the center of the table; in the photo, the Lalamove driver was wearing blue overalls, his left breast pocket bulging, and he smiled somewhat awkwardly at the camera.

Yang Lin stood up first and projected the photos of the scene onto the screen one by one. The first photo was a panoramic view of the water tank in Building 3 of Anju Community. The stainless steel tank gleamed coldly in the sunlight, the access panel cover lay to the side, and a broken chain still clung to its edge. "The scope of the on-site investigation has been expanded to the entire Building 3 and a 50-meter radius around it," his voice hoarse from staying up all night, his fingers tracing an arc on the screen. "The water tank lock was violently damaged, and the lock cylinder showed obvious signs of prying. We infer that the tool used was a flathead screwdriver, 0.8 centimeters wide." He switched to the next photo, where the edges of a size 44 shoe print on the cement floor glistened with moisture. "The suspect's footprints extended from the unit entrance to the water tank, with a stride length of 75 centimeters, a stride angle of 6 degrees, and a distinct outward gait. We estimate his height to be 178-183 centimeters and his weight to be approximately 70 kilograms."

Suddenly, a blue polyester fiber appeared on the screen, clearly visible under a microscope. "This fiber matches the composition of the deceased's work uniform lining," Yang Lin magnified the fiber details. "The cross-section is an irregular triangle, the single fiber linear density is 3.2 dtex, and the breaking strength is 4.5 cN/dtex. It was found on the fire escape door handle and in the underground parking garage." He paused, then pulled up a photo of the chain; the scratches on the chain links were particularly clear under the light. "No murder weapon was found near the water tank, but half a wrench was found in the underground parking garage drain. The model matches the tools lost by the property management, and the fingerprints on the wrench partially match the unfamiliar fingerprints on the water tank lock."

Zhang Kai opened the autopsy report, the rustling of pages breaking the brief silence. "The deceased, Zhang Guojun, male, 40 years old, cause of death determined to be mechanical asphyxiation," he read, his fingertip touching the photograph of the choroid fossa on the neck, the dark red indentation still clearly visible amidst the decaying venous network. "There are circular finger marks on the neck, 1-1.2 cm in diameter, spaced 2.5-3 cm apart, extending from the right mandible to the left side of the neck, consistent with the force characteristics of strangulation. There is a complete fracture of the right greater horn of the hyoid bone, with sharp ends and callus formation." He switched to the lung photographs, scattered hemorrhages resembling scattered red millet grains. "Tardieu spots are present in both lungs, and the cardiac blood hemoglobin oxygen saturation is 62%, consistent with typical changes in death by asphyxiation."

"How precise can the time of death be?" Lu Chuan suddenly interjected, his pen twirling rapidly across his notebook. Zhang Kai pulled up a rectal temperature curve: "Rectal temperature 19.2℃, ambient temperature calculated based on the water tank temperature of 16℃, combined with the degree of rigor mortis and the digestion status of the stomach contents, the time of death is determined to be between 8 PM and midnight on September 10th. The person ate rice and meat 3-4 hours before death." He added, "The nail of the right index finger was freshly broken, with bleeding at the break point. A small amount of skin tissue and blue fibers were extracted from the nail crevices, consistent with the polyester fiber composition found at the scene."

Wang Shuai then reported on the investigation in the community. Sixteen split-screen surveillance images appeared on the screen, each marked with a timestamp. "The community's surveillance cameras have many blind spots, especially in the fire escape of Building 3 and the water tank area," he said, zooming in on a blurry figure in the image. "At 9:17 PM on September 10th, the surveillance camera near the water tank captured a suspicious person wearing a black jacket and carrying a silver suitcase. The gait matched the footprints at the scene. However, due to the limitations of night vision mode, facial features could not be identified." He switched to the surveillance footage from the underground parking garage. "At 10:23 PM on September 10th, the man stayed in the garage for about 15 minutes and made wiping motions on the floor, which matches the time of the bloodstain wiping marks we found."

“Li Baohua, who was the focus of our investigation, has been cleared of suspicion,” Wang Shuai said, pulling up Li Baohua’s business trip certificate. “He did appear in the community on the afternoon of September 10, but he was visiting his ex-wife, and there are hotel check-in records and proof of an online company meeting, so he had no time to commit the crime. The fibers of his clothing do not match the pure polyester found at the scene, and DNA comparison also ruled out a connection.” He sighed, “But we found that Zhang Guojun’s last delivery address was Unit 2, Building 3, and the recipient was Li Qiang, and the two had a dispute over shipping fees.”

Zhang Hui laid out Zhang Guojun's delivery route map on the table, and drew a straight line between Building 3 of Anju Residential Area and the East Gate parking lot with a red marker. (End of Chapter)