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

When the call was connected, Lu Chuan said, "Retest all the asphalt samples! Focus on analyzing the unconventional additives! The murderer dumped the body in the cornfield, perhaps not to hide the body, but because it was close enough to a special place!"

The exhaust fan in the laboratory made a monotonous hum. Wearing goggles, Yang Lin carefully placed the asphalt sample into the gas chromatograph. In the slender glass tube, the dark brown substance slowly moved forward under the propulsion of the carrier gas, and the curve on the display began to fluctuate slightly. "Pay attention to this peak shape." He pointed at the screen and said to his assistant, "There is an abnormal absorption peak at the retention time of 12.7 minutes. This is definitely not the composition of ordinary road asphalt."

Yang Sen came over with an infrared spectrometer and scanned another part of the sample. As the instrument was running, dense spectral lines unfolded on the screen. He suddenly circled an area with a red pen: "There is an obvious CO stretching vibration peak at 1120cm. Combined with the results of gas chromatography, this is the characteristic absorption of diethylene glycol monobutyl ether!" The two looked at each other and saw excitement in each other's eyes - this additive is only used in high-temperature industrial asphalt, and it is not added in ordinary road construction.

Lu Chuan was studying a map when he received the call. He immediately called the whole team together and said, "Focus on investigating the Hongyuan Steel Plant in the west of the city. Their slag treatment pool uses high-temperature asphalt. Wang Shuai, lead the team to the factory and check all work-related injury records and resignation files in the past five years. Zhang Hui, contact the Labor Protection Products Association to check the manufacturers of diamond-shaped grid-patterned labor protection shoes."

When Wang Shuai and his five team members arrived at Hongyuan Steel Plant, it was the shift change. The machines in the plant were roaring, and the air was filled with a pungent metallic smell. Under the coordination of the security department, they entered the archive room, where thick kraft paper bags were piled up like mountains, each of which recorded the work files of the workers.

"First, let's look for the work-related injury records from 2018 to 2023." Wang Shuai put on gloves and started looking through them with his teammates. Time passed by, and the only sound in the archives was the rustling of papers. When he turned to the March 2019 file, a name caught Wang Shuai's attention: Zhao Jianguo, male, 3 years old, a maintenance workshop worker, suffered a third-degree burn on his left waist due to the explosion of the protective layer of the slag pool.

"That's it!" Wang Shuai immediately pulled up the photo in the archives. Although the photo was a little blurry, the figure of the man was very similar to the outline of the deceased restored by the forensic doctor. More importantly, the medical records showed that the injured person refused the hospital's suggestion of skin grafting and chose to treat the wound himself - which was completely consistent with the irregular burn scar on the left waist of the deceased.

To further confirm the situation, Wang Shuai found the doctor who attended the hospital at that time. In the medical records room of the Municipal Burn Hospital, the yellowed medical records clearly recorded: "The patient had a large area of ​​burns on his waist. It was recommended to transfer to another hospital for skin grafting surgery, but the patient refused due to financial reasons and signed to leave the hospital." The doctor recalled: "This patient was very stubborn. He said that his family had no money and insisted on going back to recuperate. I never saw him again."

In the staff dormitory area of ​​the steel plant, Wang Shuai visited Zhao Jianguo's former coworkers. "Old Zhao was an honest man." An old worker with gray hair recalled while sitting on a small stool, "After the burn, his waist was not good and he could not do heavy work. After the Spring Festival in 2020, he said he wanted to go back to his hometown to take care of his sick mother, and we haven't contacted each other since then."

"Was there anything unusual before he left?" Wang Shuai asked.

The old worker scratched his head and said, "Nothing special, but he always sighed and said that life was hard during that period. Oh, right!" He suddenly remembered something, "A few months before he left, he often interacted with a security captain named Li Qiang. That Li Qiang was not a good person. He was later fired for stealing things from the factory."

This clue cheered up Wang Shuai. After returning to the police station, the technical department quickly found out that Li Qiang was fired for embezzlement three years ago and now runs a waste recycling station. However, there is no evidence that he is related to Zhao Jianguo's death, and this clue needs further verification.

In the forensic laboratory, Zhang Kai was doing the final confirmation work. He compared the fingerprints in Zhao Jianguo's file with the fingerprints of the deceased. Seeing that the characteristic points of the two fingerprints overlapped perfectly, he finally breathed a sigh of relief: "It can be confirmed that the deceased is Zhao Jianguo." Lu Chuan stood in front of the whiteboard, pasted Zhao Jianguo's photo in the center, and wrote "The identity of the deceased has been confirmed" in red pen. But his expression was still solemn, because the next task was more difficult - to find the real murderer who killed Zhao Jianguo and restore the truth of the case. Under the lights of the conference room, a new round of investigation deployment was in full swing, and what awaited them would be more complex and difficult challenges.

The autumn rain was drizzling down, and Wang Shuai and his team members were holding umbrellas and walking on the muddy road in Qingniwa Village, Zhao Jianguo's hometown. Under the old locust tree at the entrance of the village, several villagers were sitting together chatting, and when they saw the police car coming, they all cast curious glances.

"Fellow villagers, we are from the criminal police team. We would like to ask you about Zhao Jianguo." Wang Shuai showed his police badge, sat down on the stone pier, took out a pack of cigarettes and handed them to everyone one by one.

Uncle Li took the cigarette and took two puffs. He frowned and recalled, "Jianguo had a hard life. He lost his parents when he was young and was brought up by his grandmother. He was a very honest person. He would greet everyone with a smile and never got angry with the villagers."

"He later went to work in the steel mill. Was there anyone from the village who went with him?" Wang Shuai opened his notebook, the tip of his pen hovering over the paper.

"There's a guy called Chen Erzhu, who I grew up with. He also works at the steel plant. But Erzhu went back to his hometown to build a house last year, and now he's working as a freight forwarder in town." Grandpa Li pointed in the direction of the west end of the village. "His house is at the very edge of that row of new houses."

After Wang Shuai thanked him, he led his team to Chen Erzhu's home. In the yard, Chen Erzhu was squatting on the ground changing the tire of a tricycle. When he heard footsteps, he looked up with a surprised look on his face: "Comrade police, what do you want from me?"

"I want to talk to you about Zhao Jianguo." Wang Shuai walked into the yard. "You two worked together in the steel factory, so you should know him well, right?"

Chen Erzhu put down the wrench, patted the grease on his hands, and sighed: "Jianguo is a down-to-earth person. He never slacked off when working in the factory. The burn injury was very devastating. After the injury, his waist became injured and he could not do heavy work. He was often criticized by his superiors. But he has a good temper and never argues with others."

"Has he ever had a grudge against anyone in the factory? Like, have they had a dispute or something?"

Chen Erzhu thought about it seriously, shook his head and said, "Really not. If someone in the factory bullied him, I would definitely help him. But the strange thing is that before he left, he was always close to a security captain named Li Qiang. That Li Qiang was not a good guy. He loved to take advantage of others. Later, he was fired for stealing scrap metal from the factory." (End of this chapter)