According to the distribution of blood, it should have been injected via a needleless syringe. I asked Zhang Keying to help with an X-ray diffraction analysis. Zhang Keying said, "I originally thought it was an arsenide, but it's different after the analysis. This guy is quite something, to be able to completely mask the real poison with another interfering substance."
"Could it be that even our great forensic doctor Zhang is stumped!" I teased deliberately.
"Do you think I'm a fairy? Don't you know the art of autopsy? Why don't you examine it!"
"You're mistaken, autopsy is far inferior to Western forensic medicine in verifying chemical poisons. This is your strong suit!"
"Heh, thanks for the compliment, but it's true. Without precise instruments, ancient techniques wouldn't know what these toxins are. This is the significance of chemical testing for criminal investigation techniques."
"Stop talking, you two, it's like old professors discussing academics," Xiao Dong said a bit embarrassed. Xie Chuchu beside him couldn't help but laugh.
I clapped my hands, "Everyone, be serious. Try harder and see if you can verify the specific components of this poison!"
"Okay!" The few of them answered seriously. I walked out of the laboratory. The case of the burly man had to continue. As for the poisoning case in Guwu Village, I'd let Xie Chuchu and the others verify it for now.
Seeing me come out, Liu Yuning brought me to the Information Technology department. He Xin was still tracking the burly man, but she told me that the surveillance was probably useless now, as the burly man hadn't visited the drug rehabilitation center recently.
"It seems they discovered it long ago. This guy is quite smart. How did he figure it out?" I muttered.
"Could it be that we were being monitored when we went to the drug rehabilitation center?" He Xin speculated.
Liu Yuning said, "That's highly possible. Should we give up investigating the drug rehabilitation center?"
"Let's put the surveillance aside for now. I think that burly man will commit more crimes. We can only wait."
"Sigh, it's really a headache. Do we have to wait for the next victim before we can continue the investigation?"
I didn't answer, sitting quietly on the chair. No police officer wants to see this happen, but facing such a difficult case, all we could do was endure.
For some reason, I thought of Xiao Yuanba. I strongly suspected that he was the one instigating Zhang Erniu. I really wanted to arrest him for the last case. First of all, this guy is very likely the mastermind behind providing the poison. Given his intelligence, lurking in the school as an ordinary chemistry teacher, we couldn't do anything to him.
Moreover, he is Xiao Yuande's brother. I have always had this concern, which has hindered the investigation from proceeding smoothly.
Liu Yuning and I went to Xinyu Middle School, where Xiao Yuanba was located. After inquiring, we learned that he hadn't come to class and was resting in his dormitory.
However, I saw it was Sunday, and his rest was normal. When we found his dormitory, I knocked on the door. When the door opened, he saw us, and Xiao Yuanba showed a slightly strange expression. His brown eyebrows were stretched incredibly straight. "What are you doing here?"
"Xiao Yuanba, long time no see. How have you been?" Liu Yuning began. I stared at him intently, my face showing anger.
"Still the same. I don't know what wind blew you here. You two police officers, you don't suspect me of doing something again, do you? I'm usually very busy with classes and don't have time to think about other things!"
"May we come in?" Liu Yuning asked.
"Of course, but my dorm is a bit small. If you two don't mind, please make yourselves at home!" Xiao Yuanba said, moving aside. He walked into the living room without any fear, made us tea, and then sat down.
I said, "We've recently been investigating Guwu Village, Teacher Xiao. I wonder if you still remember this place?"
"Guwu Village? Is this a wuxia novel? I haven't heard of it!" Xiao Yuanba pretended to know nothing. But I could see a strange glint in his eyes. This guy clearly knew. I remained calm and continued, "Someone once used a very subtle toxin to poison the lake. Everyone in the village died, with only a few surviving. These few people came to the city and were doing alright, but recently they've been threatened by someone. This guy knows these people's backgrounds very well and has set up various criminal methods for them to serve him. I don't know how this guy did it. His control ability seems very strong, but he usually appears very low-key."
I was speaking indirectly, constantly staring at Xiao Yuanba's face. Several times his lips twitched irregularly, though subtly, I still observed it. This guy is definitely the mastermind, but we couldn't get any evidence of his connection to Zhang Erniu and the burly man.
Seeing that he wasn't speaking, I stood up to search his house. However, he said, "Your story just now was quite good. Have you written a new work again, writer He!"
Xiao Yuanba didn't take what I said seriously at all and deliberately teased me.
"Xiao Yuanba, don't think you can fool us like this. We know what you've done!" I suddenly got angry.
"Oh really? What could I have done? I'm just an ordinary chemistry teacher. Why do you suspect me!"
"You're hiding it very well. Do you dare let us search your house?"
"It's fine, search if you want!"
From beginning to end, Xiao Yuanba appeared very calm. Liu Yuning and I exchanged a look. Although the possibility of finding anything was slim, I still insisted on going to his room. I found a computer and turned it on. There was no password. I pressed a key, and Xiao Yuanba actually came in, "Officer He, please don't touch my games. I have to play one round every night before I can sleep!"
"Don't worry!" I said nothing, inserted a USB drive, and fumbled around. However, I didn't find any chat logs or useful data. There were no traces of deletion on his computer either. I thought he definitely didn't use this computer to contact these criminals.
"Give me your phone!" I commanded.
"You're checking my computer, and now my phone? Do you have a search warrant? Just like this... " I thought Xiao Yuanba wouldn't give me his phone after saying that, but he directly took it out and handed it to me.
I took the phone and checked it again using the same method. Then I said, "Do you have another phone? I'm taking this phone and the computer back!!"