Transcript for Husband charged with wife's murder blames cold medicine

Thank you, Ian. We want to move to the husband facing murder charges in a bizarre case. Authorities are pointing to a chilling 911 call. The caller saying he woke up from a dream and was horrified at what he saw. ABC's arierielle reshef is here with more. Reporter: Raleigh police are investigating the twisted murder of a recent bride. The caller telling police cold medicine may have done it. Matthew Phelps arrested after a detail and disturbing call to 911 early Friday morning. I had a dream. And then I turned on the lights and she was dead on the floor. How? How? Reporter: Between lay board breaths, a stunning admission. I have blood all over me and there's a bloody knife on the bed and I think I did it. I can't believe this. Reporter: A distraught sounding caller telling the dispatcher he took medication to sleep the night before. What dead sin did you take? I took plp blp. I know it can make you feel good. A lot of times, I can't sleep at night. She's not moving. Oh, my god, she didn't deserve this. Reporter: Just after 1:15 A.M., officers arrived at the cupable's Raleigh town home, discovering 29-year-old Lauren Phelps with stab wounds. He qualifies yes, it look like I did kill her. The knife is here. I have blood all over me. However, this medicine made me do it. It's not an uncome way for the people in his position to respond. It's like, I've got to think of something immediately to sort of mitigate a really horrible situation. Reporter: A close friend saying Lauren was a Sunday school teacher. Matthew studying to be a pastor. The two were married less than a year. ? The key is, what is the real motivation here? Reporter: And police say while an investigation Sunday way, they believe the crime was not a random act. Right now, math Yi Phelps is being held without bond. He's due in court on Tuesday. A horrifying story. Thank you. Let's switch gears and get

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