Sheeda Derek News Today : Breaking News, Live Updates & Top Stories | Vimarsana

>> okay. show me a picture then. >> reporter: you showed him a picture of annie. >> yep. >> brittany? do you mean brittany? >> no, it's annie. >> reporter: detectives thought daniel was lying, and they were done playing around. >> what if i told you she's dead? >> i didn't do it. what the [ bleep ]? if you guys think i did this, i do want a lawyer. >> okay. >> because there's only -- >> we're done. >> the only thing that is shaking me. >> we're done, daniel, because i think you did it. >> well, if you think i did it, then you've got the wrong guy, man. for real. >> good luck. >> find the right...

He couldn't take his eyes off of me. and i thought, this kid has done something wrong. and he thinks i'm coming to arrest him because i'm approaching him in uniform. >> reporter: did you share that with derek? >> yes. he said, we've received more information now, and we think we have another suspect. >> reporter: another suspect. a new name altogether, based on information from an eyewitness who may have seen annie kasprzak the night she was killed and knew who killed her. coming up -- is this how annie was murdered? and is this the man who murdered her? when "dateline" continues. when "date...

So, derek, he was a good guy, good cop, good friend. >> reporter: derek was just 32 years old, leaving behind his wife, his 6-year-old sorngs and his family at draper p.d. >> you know everybody talks about a cop's cop and the best cop you can have and how he treated and served the community. derek was one of those guys. >> reporter: for jaclyn moore, the loss was two-fold. >> he was starting to get some free time to come help me with the case and tell me more about what he did when he was on the case. and then he was killed. i didn't have anyone else to ask. >> reporter: you'd lost your friend...

By neighboring west jordan p.d. during her interview, she started telling detectives about a young girl she had seen a week prior. the cops thought some of what she said sounded eerily similar to annie's case. so they called draper p.d., and detective derek johnson and his colleague came over to hear what joanna had to say. >> tell me what you know about this girl. >> it was the second time i've seen her over there. >> reporter: there at the home where a man named daniel ferry used to live. danny ferry is a guy known to law enforcement? >> yes. >> reporter: as maybe a drug dealer? >> drug deal...

>> their jane doe dressed in a red and white plaid shirt looked to be about 20 years old, her features possibly asian, and obviously she had been murdered. leading the investigation was a young detective named erik johnson. >> tell me about him. >> right when he came into the academy he sat next to me and started teasing me. and the rest of the class time we just harassed each other and laughed and giggled all day. >> reporter: jaclyn moore met derek at the police academy. sheed a derek hit it off immediately. >> he applied for detective and got it immediately. >> whdid you think rats, he got ...