Transcript for Brendt Christensen arrested in connection to Yingying Zhang’s disappearance: Part 5
It was close to midnight. Mr. Christensen agreed to come and interview with myself and detective Stiverson, with the university police. We left his apartment and drove back to the FBI headquarters. Did he look like he was worried? He was very calm. My name is Anthony Manganaro. I'm a special agent with the FBI, I'm assigned here in champaign, and then this is Eric. Yeah, detective Eric Stiverson. Detective with the university police, okay. We are investigating the disappearance of Ms. Yingying. I'm willing to answer questions, some questions, obviously, I don't know -- One of the things I like to do when I start an interview is just have the person tell their story. Or in this case, retell his story that he had prior told to agents. Do you remember what you told him? I was either playing video games on my computer or taking an afternoon nap. Was he abnormal, the way he was answering? He didn't seem very concerned of why he was there. Most people in that situation might be like, you know, why are you pulling me out of bed at this time in the morning? Why are we here? And he never really asked that? He just was just kind of wanted to see what we were gonna ask him. Almost like he felt he was interviewing you. In a way. He wasn't gonna provide us anything new, and he wanted to know what we knew. Why am I under suspicion? Is it just my car or is there anything else? I mean that's, you know, a large portion, I mean, it is a very unique car. Detective Stiverson and I hadn't interviewed together before. We were very comfortable with doing it together. We pretty quickly and easily evolved into a softer approach for myself. What did you graduate in? Masters in physics. Wow, that's way smarter than me. Thanks. And a bit more confrontational approach with detective Stiverson. Look, you know that we didn't bring you all the way up here to talk about video games and what you had for lunch that day. Yup. Why do you think that we brought you up here? Because the car I own was seen picking up a girl that's missing. Boy, I was really going after him, and it was because I had a sense of urgency that, I needed to know where she was, like, now. I really pressed him about the video, "You're a student here at the U of I. What do we have everywhere?" I'm like, "Cameras, brendt, cameras. We have cameras everywhere." We control kiosks of bus stops. We can look in buses, we can look in every building, out on the streets. And you're telling me that I didn't see you driving your car on Goodwin? And then you turned, you turned on Clark. And we still have cameras. I've seen the videos, but I didn't see me. You've seen what we've allowed you to see. And then at that point, you could see it in his face. The wheels are turning. His eyes start to flutter. I know that you picked her up. Where did you drop her off at? She was looking for a ride, she had missed her bus. She told you she was going to one north, so where did you drop her off at? There is a lengthy period of silence. Mr. Christensen starts to physically react to that confrontation when he realizes he's at odds with his story. He's almost hyperventilating like somebody that's having a panic attack, and at one point, he looks over to Tony. Mr. Christensen even looks at me, almost wanting help, almost wanting an out. And I remember just staring back at him because I wanted the answer as well. I wasn't there to give him an out. Maybe I'm getting my days mixed up then. Okay. I thought I drove, I thought I drove around on Saturday. I did pick a girl up, I don't remember where. Okay. He made an admission that was like a light bulb going off. He changes direction and admits that he actually had picked up an Asian person in his car earlier in that day. He had gone from that cool, calm, confident to nervous. I saw her picture. I don't think it was her though. And seemed to desperately be looking for an answer to give that would explain why she got into his car. Do you remember the girl's name that you picked up? No, she was talking very broken English. Okay. Tell us about what happened. What time of day was that? Early afternoon. I don't really remember. Okay. I was just driving around. I saw a girl and she was very distressed. I asked her if she needed help, I talked to her for a little bit, not that much. I gave her a short ride. A couple of blocks. She freaked out and got out. Okay. And that's all it was. He says, "Oh, I did pick up an Asian female." And then the information that he provided pretty much narrowed it down to it was yingying. You have no doubt at that moment? No doubt in my mind at that point. I knew that he was our guy, that it was not only his car, but he was the driver. Christensen was our guy, but we still didn't know where yingying was. We still didn't know what happened to yingying. So where did you drop her off at? Where'd you take her, brendt? We need to find yingying. Tonight. I think it's time that I stop answering questions. I know the typical advice is to get a lawyer before you answer anything, and I think I've tried to help enough. I knew we had the guy. What I struggled with was being able to prove it. He was arrested for making a false statement to the FBI. He was detained for about 24 hours, but ultimately the U.S. Attorney's office decided to not prosecute. We didn't want to hold him in custody because we thought that, by releasing him, we would have the opportunity to find yingying. The authorities are trying to find her if she's still alive. They have a secret game plan. They are going to have somebody very close to Christensen go undercover and help them solve the case. I know everything. Well, I know way more than everyone outside of, like, you know, the FBI and the police.
This transcript has been automatically generated and may not be 100% accurate.