Viewer discretion is advised. A shocking case unfolded in Hyam, Florida. Authorities say 13-year-old Derek Rosa dialed 911 to confess that he had fatally stabbed his mother, 39-year-old Arena Garcia, as she slept beside her newborn daughter. >> Uh, no, I'm not hurt. I just have a little bit of blood on my hand. >> I need to know if your mom is is breathing. >> She said miss. >> Okay. And why did you do that? >> Blood all over the floor. >> Where is your sister? Your sister is still there. >> She's sleeping. >> She's sleeping. Okay. >> Excuse me, miss. What do I do if if she wakes up? >> If you wake up, just let me know. I need to know. Do you think we can help your mom? >> Miss, she's dead. I took pictures and I told my friends about it. Was that bad? >> You told who about it? >> My friend. >> Who did you send us pictures to? >> My friend. I don't know his real name cuz he is an online friend I play with a lot. >> Officers, I see officers. Do I leave? Do you leave my house? >> Do not leave. >> Put the phone on the floor and go outside with your hands up in the air. Okay, here comes the ground. Get on the ground. Go, go, go, go, go, go. Slow, slow, slow. >> Body camera footage captured the moment officers entered the family's apartment. Rosa, wearing pajamas, stepped into the hallway. Officers shouted for him to raise his hands before forcing him to the ground and taking him into custody. Investigators have yet to determine a motive. The following video captures investigators questioning Derek Rosa as he describes the attack in his own words. >> So, you went to sleep around 10:00? >> Yeah. >> Okay. And then what? I woke up. >> You killed her. All right. Um, what type of what type of knife was it? Do you know? >> It was just a big size kitchen knife. >> That big? >> Yeah. What color was the the the handle? >> Purple. >> Purple. >> Yes. >> Okay. Uh your mom was sleeping. >> Yeah, she was sleeping. >> Okay. Um explain to me Well, we'll get into that a little later. What did you do uh after you killed her? My stepdad has I mean he owns two guns. He has a Glock 19. >> Okay. >> And then uh I don't know what you call it. Another one. >> Okay. What color are they? >> The Glock 19 is black and then the other one has a silver slide and then like a dark bluish handle. >> Okay. Um so what did you do with the guns? He always has his garage with him at all times. >> Mhm. >> And since he's a truck driver, he wasn't at home. He was far away. >> Okay. >> So, I went into the closet. >> Mhm. >> I found his because he goes shooting at gun ranges. >> Okay. >> I grabbed the gun. >> I put the magazine in the gun. >> I pulled back to slide, but I wanted I didn't want to shoot myself. >> Okay. >> I intend to shoot myself before, but I couldn't. >> Okay. Um, and then what did you do? >> I decided to call my friends to tell them what happened and then I said goodbye to my friends. >> You called them before you decided to try to shoot yourself or afterwards. >> After. >> Okay. How many friends did you call? >> Only one. >> What's his name? >> I don't know his real name. He's an online friend. >> He's an online friend. >> Yeah. When you say online friend, what do you mean from video games? >> Yes, from video games. I know him real well. >> Okay. How long have you known him? >> Since like I was 10. 3 years. >> 3 years. Have you ever met him? >> No, I've seen his face. >> You seen his face? >> Yeah. >> So, how did you communicate with him? >> My cell phone. >> Through your cell phone. So, you have his number? >> Yes. >> And you don't have him stored under a certain name or you have him stored under a gamer tag? >> I have I made up a name for him. >> You made up a name for him? What name did you make up from? >> Sweden. >> Sweden. >> Sweden. S W E E D E N. >> Okay. How often do you talk to Sweden? >> Every weekend. >> Every weekend. >> Yeah. >> Okay. So, you called Sweden. And what did you tell Sweden? >> Tell them what I did. >> What exactly did you tell Sweden? When you say what I did, did you tell them how or no? How you killed her or no? Okay. Did you send them any pictures? >> Yes. >> Uh, how many pictures did you send them? >> I sent him two of my mama and one of me. >> Okay. Um, did you What did he tell you? >> Said he couldn't believe it. Okay. Does Sweden live down here in Florida? >> Real far. >> Real far? >> Yeah. >> In America though? >> Uh, in America? >> Yeah. >> Okay. So then you you hung up the phone, >> say goodbye. >> Okay. And then what did you do? >> I was going to show myself that, but I said it. I didn't want to do that. And I called 911. >> Okay. And what did you tell 911? Okay. >> And they kept you on the phone? >> Yes. Until the cops came? >> Until the cops came. >> Do you remember what else you told uh the 911 oper? >> My address, my name, what I was wearing. >> Okay. >> And my age and my date of birth. >> Were you wearing the same clothes you're wearing now? >> Yeah. >> Uh there's some red stains there. Is that blood? I >> think it is. >> Okay. >> And a little bit of blood on my hands. >> On your hands, too? >> Yes. >> Okay. Um, uh, did you ever make your way to your sister? Like >> killing her? >> No. >> Touching her. >> Touching her. >> No. >> No. >> I left her alone. She was sleeping and she didn't wake up, so I didn't touch her. >> Okay. All right. Uh, let's get back to your mom. Okay. You said she was sleeping. >> Yes. >> Okay. Where exactly did you cut her? According to reports from prosecutors and court hearings, investigators said Ina Garcia was stabbed multiple times, 46 stab wounds in total. And Derek Rosa indicated during interrogation that he stabbed her in the neck while she slept. >> Okay. And and um you purposely went for the artery when you cut her. >> Okay. Um and then she woke up. >> Yes. Did you say anything else to her? Did she say anything to you or No, >> no, she just screaming. >> She just screamed? >> Yes. >> Okay. Um, why did you stab your mom? >> I go to the bathroom before I answer that. >> Yes, of course. >> Um, so you were about to tell me the why. Why did you uh kill your mother? Do you know? Do >> I have to say it now? >> Yeah. Get it off your chest. Absolutely. >> Can I wait for a lawyer? >> Okay. At this point, you want a lawyer? >> Maybe not. >> We We can't. No. Listen. Listen. Just so you understand. Okay. You have mentioned or asked us, should you wait for a lawyer? We're not here to advise you on whether to talk to a lawyer or not. That decision is yours. Okay? But if you are requesting a lawyer at this point, we can't interview you any further. You understand? We have to stop the interview. >> Okay. >> Do you want us to stop the interview? >> Yes. >> Okay. And then this interview will end right now. >> It is 3:05 a.m. >> Okay. Under US law, once Dererick Rosa asked for an attorney, detectives were legally required to stop questioning him and the interrogation had to end. The teen calmly described the size and color of the knife, showed detectives his bloodstained hands, and confirmed that his mother was asleep when he attacked. He said she screamed as he stabbed her before asking for a lawyer. Rose's attorneys have suggested they may pursue an insanity defense. His grandmother, devastated, told police in Spanish that she had never seen signs of mental illness. "He was a normal, intelligent kid." She said, "I don't know what happened. All I know is I don't have a daughter anymore." Rosa pleaded not guilty in December 2023, but interrogation footage painted a disturbing picture. In a later hearing, prosecutors played a chilling recording. Rose's own words, "I woke up. I grabbed one of the kitchen knives and I went to her room. I killed her. The judge ordered him held in an adult jail while awaiting trial. Evidence revealed even more. Surveillance footage from a baby cam showed Rosa standing over his mother as she slept moments before the attack. Investigators say she was stabbed 46 times. Afterward, Rosa allegedly took a smiling selfie with blood on his hands, sending it to a friend before asking a 911 dispatcher if what he'd done was bad. He also admitted to finding two of his stepfather's guns and considering suicide, but never following through. Detectives later uncovered online searches on Rose's devices, queries about the most effective way to kill, and whether a small knife could cut through bone. For a family that once described him as a good kid, the reality was almost impossible to comprehend.