>> then terrible news. a student had been murdered. >> the girl on the floor had very black colored hair. she had lighter hair. >> who was it and where was alex. >> at that point, it was perhaps one dead and another missing. >> the killer could be roaming the campus. >> a mysterious tweet. >> what do you think it meant? >> i don't know. >> my son just called. >> and a terrible truth. >> i didn't know how? i didn't know who? i didn't know anything. i just know she was gone. welcome to "dateline" a college freshman found brutally beaten, so gruesome, they couldn't identify the victim but they could identify the suspect. he tells why he did it. here is andrea canning with "after midnight. >> every year as summer fades into fall and lazy days at the beach come to an end, students flood back to college. the same scene year after year at campus after campus. every year, there's that new bunch, the freshman. >> i was nervous that first day. >> all those worries. all those questions. >> do i really have to go to these classes and what is this class like. they are not quick adults or teens. suddenly, there on their own. >> most of the time, kids sail through the experience, date new people and move on. but there are others not so lucky. they are the victims of a troubling trend that caught the nation. dating violence. >> this could happen to anyone's daughter? >> anyone. >> it was late september, 2012, the college at brockport, the state school in western new york. 18-year-old alexandra was having the time of her life. >> as soon as i met her, i knew we were the perfect match. >> they met within days of arriving. besties from the beginning. >> you really clicked? >> i did. why did you like her right away? >> i could act so funny or myself. if i had a problem, she was there for me. >> by late september, they were inseparable, swapping clothes and confidences. on friday september 28, they were going off in separate directions. samantha heading home to see her family. the other, remaining on campus. that afternoon, she went down to the dorm room to say goodbye. >> it was around 3:00, i was about to go home. >> she said, can i pick out some clothes in your closet. i said sure. she took three of my shirts. she was so excited. her boyfriend was coming to spend the weekend. but first alex had a swim meeting. she had been swimming since high school where page was the cap pin. >> you were the captain but you called alex the heart. >> in high school, she wasn't the fastest but one of the most important people on our team because she had the most heart. >> that friday, the team meeting ran late. >> alex texted to apologize. please don't kill me, she wrote. don't worry, he answered. midway through the evening, samantha texted alex. >> i told her, can't wait to see you tomorrow. love you. good night. she said the same. >> later, in the early hours of saturday morning, samantha awaken by a call. >> she was scared. she didn't know where alex was. >> she had a sign. i don't know how she knew something was wrong. >> her mother thought something was wrong and called you freaking out? >> yes. i was like, i'm home. i don't know. >> a frantic mother searching for her daughter. what happened to set her off and why she was so distraught. >> a good friend of her parents. page's mom. >> they had gone off for a weekend vacation and been texting that evening becky was sending pictures of the hotel room and you say, oh, great. alex didn't respond. hours later, that was not how their relationship worked. >> is that possible in college. >> i imagine the first couple times maybe, when it was several, that raised flags. >> a little bit of mother's intuition? >> i imagine it was. >> her mom worked the phone franticly. finally at 2:41 a.m., she called the campus police to ask them to check on her. >> you took that call? >> i did. >> you headed over to the dorm. and what happened? >> i went there and knocked on the door. i knocked twice. since it was a welfare check, i said let me see if it is unlocked. >> it was. the officer will never for get what he saw in that room. >> what happened in roam 108. police were about to confront a frightening and confusing scene. >> you never come to work thinking you are going to see something like that. >> they were telling everyone keep your door shut. >> when after midnight continues. r midnight continues. nurse mariyam sabo knows a moment this pure... ...demands a lotion this pure. new gold bond pure moisture lotion. 24-hour hydration. no parabens, dyes, or fragrances. gold bond. champion your skin. we're carvana, the company who invented car vending machines and buying a car 100% online. now we've created a brand-new way for you to sell your car. whether it's a year old or a few years old. we wanna buy your car. so go to carvana and enter your license plate answer a few questions. and our techno wizardry calculates your car's value and gives you a real offer in seconds. when you're ready, we'll come to you, pay you on the spot and pick up your car, that's it. so ditch the old way of selling your car, and say hello to the new way at carvana. find your rhythm. your happy place. find your breaking point. then break it. every emergen-c gives you a potent blend of nutrients so you can emerge your best with emergen-c. officer michael johnson, a cop at the college at rock port was on a routine welfare check early one saturday in september 2012 when he got the shock of his life. >> we don't see that level of violence that often. >> room 108 was wrecked. there was blood everywhere, on the bed, on the door, on a pillow on the floor. and in the center of the room is a young woman on the floor facedown. her bloody hair falling over her face. >> it seemed very unnatural the way she felt. even the bloody footprints that were around her indicated something violent happened. the adrenalin kicks in and you need that in that moment and it was just time to go to work. if she was alive, i had to do all i could for her. >> i heard this guy yelling and i thought it was a drunk college kid. >> reporter: hailey lived across the hall from alex's room. the commotion woke her up. >> i noticed the man was yelling for help and stuff. so, i woke up and started looking through my peep hole and it was a police officer yelling. >> lieutenant worked with officer johnson on the campus force. >> he radioed me for the ad -- >> what's that? >> the defibrillator. >> what did you think when you saw what you saw? >> i couldn't believe it. you never come to work thinking you're going to see something like that. >> hailey was glued to her peep hole. she saw people everywhere. >> they were saying keep your door shut, don't come down the hall and we didn't know what ways going on. >> hailey was fielding a storm of texts from worried students. >> everyone was so confused. i don't know if somebody's hurt. >> reporter: by new the cops realized the young woman on the floor was dead. >> what happened was the ambulance showed up. and the police officer said to the paramedic we only need one of you to go in and to pronounce her and the paramedic came out and pronounced her jane doe and it was just oh, wow. i knew that meant they couldn't identify who it was and they left. and i woke my roommate up and i said somebody's dead. and she didn't believe me at first and i told her, like, they left. the stretcher had nobody on it. >> the students on their phones, trying to stay calm, but it wasn't easy. >> we were really afraid. and i mean, the police officers are like you're okay, you're safe. but we were really scared. >> reporter: hailey went over and over the events in the mind. and she remembered something about 1:15 a.m., as she was trying to go to sleep, an unusual sound. but was it related? >> a thud, thud and then maybe a pause and then it was like more and then kind another break. some louder than others. >> then as the activity in the hallway intensified, hailey heard -- >> so, at that time i knew we had to do our jobs and preserve everything for the safety of the rest of the campus. >> the officers had a million questions. number one, who was the girl lying with her face to the floor? the girl they'd been asked to check on had blond hair. the girl on the floor was a brunette. was she alex's roommate? it was hard to know. her face was bloody, unrecognizable. so, then you must be wondering where's alex? >> yeah. >> they learned she entered the dorm with her boyfriend after midnight. when they looked closer at the photos in the room, they saw a young man they recognized. in fact, they issued him a ticket that very night. >> we knew who we wanted to look for at that time. >> reporter: it was clayton whittemore, alex's boyfriend. they needed to find him and fast. >> if we have someone that did this violent act here in this specific room, you know, what is he capable of doing when he leaves here? >> coming up. a missing boyfriend, an anxious best friend. >> i rushed here. >> 4:00 in the morning?. >> 4:00 in the morning. >> there were so many things that didn't make sense in the room, it was hard to say. new vicks vapostick. strong soothing vapors... help comfort your loved ones. for chest, neck, and back. it goes on clear. no mess just soothing comfort. try new vicks vapostick. the campus cops investigating the murder in mcclain hall weren't sure who the victim was but they recognized a young man in photos in the dorm room. they'd seen the same young man when they were patrolling the campus earlier that night. >> i observed a couple coming down the street here. we could see he had an open container in his hands. i requested an id and explained we have a local ordinance that says you can't have an open container. >> the person getting the ticket was clayton whittemore, returning home from a party with his girlfriend, alex. >> he was doing small talk with the female he was with and was able to make her laugh a little bit. if anything was bothering her, she didn't let us know. >> so, just a normal couple out on a friday night? >> he just dropped it to the ground and i made a comment that could be another $100 fine and he complied and picked it up and that's when i saw him cross the street here. and at the same time the female stayed on this side of the street and they both continued to walk on separate sides of the street. >> they were both from the town of new hartford in central new york. they got together when alex was in high school. clayton had already graduated. now they were trying to make a go at long-distance relationship. >> they really wanted to make it work and stuff and i think it was working. i think she really did love him. >> what kind of things did she say about clay? >> it was kind of just little things here and there like i can't wait to see him, like i miss him. you could see in her eyes she really did want to be with him. >> clayton, number 21, had been a standout hockey player in high school. after he graduated in the spring of 2010, he spent the summer with the host family. hunter fernando was one of clayton's teammates staying with the host family. >> we never really got in trouble. >> girls? >> nope. >> partying? >> no. >> drinking?. >> no. >> this sounds like a tamest bunch of hockey players i ever heard of? >> no. >> it was hardly surprising that alex was drawn to another athlete and clayton was a catch. she'd gone through high school with clayton and sat beside him in senior year math class. >> she felt he deserved a lot more and she was very lucky. >> so, she considered herself lucky that he had chosen her? >> absolutely. >> did it seem he really cared about her and liked her, happy to be in the relationship? >> yes. you see them laughing together, getting along so well. >> their twitter messages were light hearted. they called each other dork and freak and lived out their lives in the twittersphere. before arriving that friday alex tweeted, ah, see you soon. her family liked him soon. her mom contributed $20 towards his gas for the trip. once alex's swim team meet ended that day, the couple had time. >> she's like we're out to dinner right now and they went to a friend's house and came back to the dorm. on the way back clayton got that ticket and the cop saw them back separately. and at 2:00 a.m., should have known, it read. should have known. >> what do you think that meant? >> probably does have something to do with clayton but i don't exactly know. >> minutes later alex swiped her card to enter the dorm with clayton. so, now, investigators were desperate to find out where clayton whittemore was and if alex was with him. >> luckily we had all the information from the ticket we issued him. >> what could he tell them, if anything, about what happened in the dorm room? >> i couldn't put together what happened because was so violent. there was so many things that didn't make sense. >> scenarios that you were -- >> it's an alteration between roommates. maybe possibly alex and clayton were on the run and this is the roommate on the ground. maybe clayton hurt the roommate. through your mind? >> yes. >> reporter: and at her parents' house, samantha, her best buddy, was calling all her friends. a college official got on the line and told her there was a situation. >> and i broke down and i called my sister and was like we need to go back right now. and i rushed here. >> 4:00 in the morning? >> 4:00 in the morning. i didn't know exactly who it was. >> reporter: 100 miles away a frantic mother waited desperate for answers but when the answers came they were unbearable and they were coming from the killer himself. >> coming up. two frantic phone calls from a mother. >> he said she was breathing and then she stopped. >> and her son. >> what's going on there, bud? >> i did something. ♪ ease, or ckd. did you know ckd can lead to kidney failure and dialysis? kidney alert! ckd often has no symptoms until it's too late! help protect your kidneys. call your doctor for a uacr test. it shows one of the earliest signs for ckd. visit kidneyalert.com! derriere discomfort. we try to soothe it with this. it shows one of the earliest signs for ckd. cool it with this. and relieve it with this. but new preparation h soothing relief spray is the 21st century way to do all three. even touch free. preparation h. get comfortable with it. hey hun hey, get your own vapors relax with vicks vapobath or with vicks vaposhower. take a soothing vicks vapo moment wherever you chose. it's our holiday savings event on the sleep number 360® smart bed. it senses your movements and automatically adjusts to relieve pressure points. and its temperature balancing so you both sleep just right. don't miss our weekend special. save up to $500 on select sleep number 360® smart beds, and free premium delivery when you add a base. ends monday. i'm dara brown. nbc news has confirmed 27 deaths. a state of emergency is declared in kentucky whereas many as 100 people are feared dead. a curfew has been implemented in the hardest hit locations in kentucky. president biden plans to visit the areas and offering full federal assistance. now back to dateline. a murder on a college campus. the murder so brutal, the victim couldn't be identified. early that saturday morning, steven peglo, a veteran homicide investigator with the monroe county sheriff's office was called to the campus. the cops had a murder on their hands, a body they couldn't identify and a killer on the loose. >> everyone thought they knew what was going on but they didn't until we got there and started putting the pieces together, you didn't know. >> one young woman was dead, another was missing. >> a young lady was still alive and needed help, right then that was my priority in my mind on the way out there. >> were you thinking clayton had taken alex and hurt her and she was still alive or someone else was involved? >> at that point i was thinking she was with clayton and he hurt her. >> so you're thinking we need find her? >> yes. >> reporter: but about 3:00 a.m., an operator at the oneida county emergency center got a call from a profoundly troubled dad. >> my name's scott whittemore. >> it was a stunning statement, even for a 911 dispatcher in the early hours of the saturday morning but the dad didn't know much. >> reporter: the father reported that his son was in a bad way. >> he's talking about killing himself too. i don't know what's going on except he got in trouble. >> reporter: the divorced dad admitted he was out of the loop in family matters. now he was doing his best to stave off a tragedy. >> reporter: the dispatcher asked scott to call his son back to find out more. minutes later he was back on the line. >> he was a girlfriend in brockport. his mom thinks he's probably on the way back home from brockport. >> sandy. we're trying to find your son. you think he was out visiting his girlfriend in brockport? >> what? well, he -- he's in canada right now. >> well, he's not in canada. >> he's not? >> no. at least his cell phone wasn't in canada. if you were just talking to him on his cell phone, he's not in canada. >> okay. >> just take a couple of deep breaths and we're going to try to find him to get him help. >> reporter: they got the name alex kogut from the stressed out mom. slightly wrong but enough. seconds later he was on the phone with the campus police in brockport. and finally, the pieces of the story began to fit together. >> we got a call from a father about an hour ago that said his son found him and stated he killed somebody. we pinged his phone. the suspect is clayton whittemore. apparently he went to see a girlfriend at your college. >> yeah, that's who we're looking for. i had him in an open container earlier. we don't know where this alex kogut is. we can't locate her, but the roommate is doa. >> but the roommate was dead and alex was with clayton somewhere. but then new information from clayton's mom. he said she was breathing and then she stopped. >> clayton's mother was beside herself. >> did you get ahold of the college out there? >> yeah, they're looking for him. we don't know what the heck is going on. then once more, the call line lit up at the 911 call center. >> and then once more that morning the 911 call center lit up in oneida county. clayton whittemore was on the line. >> what's going on there, bud? >> i did something. >> reporter: it was 3:44 a.m. and the truth would soon be revealed. >> coming up who had clayton whittemore killed? >> i didn't know anything. i just know she was gone. firefighter maggie gronewald knows how to handle dry weather... ...and dry, cracked skin. new gold bond advanced healing ointment. restore healthy skin, with no sticky feeling. gold bond. champion your skin. ♪ ♪ cases of anxiety in young adults are rising as experts warn of the effects on well-being caused by the pandemic. ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ before discovering nexium 24hr to treat her frequent heartburn... claire could only imagine enjoying chocolate cake. now, she can have her cake and eat it too. nexium 24hr stops acid before it starts for all-day, all-night protection. can you imagine 24 hours without heartburn? instantly clear everyday congestion with vicks sinex saline. for fast drug free relief vicks sinex. instantly clear everyday congestion. and try vicks sinex children's saline. safe and gentle relief for children's noses. clayton whittemore was at a restaurant when he called 911 with a stunning admission. >> i'm turning myself in. i did something that i can't take back and i just got to turn myself in. >> it was almost 4:00 a.m. a hunt that pulled in emergency dispatchers, college officials and two sets of anguished parents was almost over. >> two officers, two new york state troopers who were patrolling the freeway that night. >> sandra is the district attorney in western new york. >> they were called to respond right to that diwitt road service area, not knowing what to expect. at that point it was one dead than brockport college campus and perhaps another missing. >> and clayton was there waiting?. >> he was. he walked over and said i'm turning myself in. they noticed bloody sneakers and blood on his hands. >> reporter: within 20 seconds clayton whittemore was cuffed and in custody. >> they wanted to check the trunk because at that point they hadn't determined who it was on the dorm room floor of room 108. >> that was about to change. the cops back in brockport, who initially thought the victim might be alex kogut's roommate learned the roommate was staying elsewhere that night. but where? they started an urgent search. until they spoke to her, they couldn't be certain of the victim's identity because of the hair color. >> the girl on the floor had almost dark colored hair. but when you saw the photos of her and clayton in the dorm room has light colored hair. >> the roommate had darker hair. investigators knocked on students doors. >> then a nugget buried in a conversation. they learned alex recently dyed her hair brown. they had what they needed to id their victim. now they wanted to hear from one more person, alex's roommate. when she did call in, finally, they learned she was staying in another dorm room. we had her come to us to speak to her. positive the girl on the floor was alex kogut. bubbly, happy, alex kogut. only 18 years old. best friend samantha was devastated. >> i broke down and i knew at that point, my life was changed. >> reporter: you knew without anyone telling you? >> uh-huh. i didn't know who, how, anything, i just knew she was gone and i could never see her again. >> reporter: they're family friends of the koguts. her roommate woke her up around 7:00 that morning. >> she said we have to go. we're all meeting together. something happened. she said something happened to alex. i said alex what? she said it's a terrible accident and i said well, is she okay and she said no. i said is she in the hospital and she said no, mom. she's not. and i said has she died and she said yes. so, i was shocked and all i could think was what could have happened to alex in her dorm room? >> they were asking clayton whittemore that very same question that very same morning. clayton put the pieces together for the police about what happened that night. and it began with the fact that his relationship with alex wasn't so good afterall. the couple had dinner, then the party. clayton said he and alex drank moderately. but at the party, he got annoyed with her, said he felt disrespected. >> reporter: as they walked back from the party, clayton got that open container ticket. clayton, remember, walked to the other side of the street to cool off and then alex posted that final cryptic tweet, "should have known." >> we'll never really know what that meant. >> what do you think it meant? >> maybe we weren't meant to be together. maybe we should break up. >> reporter: clayton said they were fighting about cheating. old stuff, he called it. >> then he told the cops she got physical. >> she started pushing me and pushing me and kept doing it. >> reporter: but the investigator pointed out clayton was a strong guy, alex was tiny. >> reporter: he told the cops he asked her to stop but he said she wouldn't and when he offered to leave, she told him to stay. and then this. >> reporter: the attack that followed was savage, unthinkable. in a tiny dorm room, surrounded by sleeping students, clayton whittemore beat his girlfriend to death. investigator peglo has seen plenty of homicide scenes but none like this. >> they're like i have blood on this and give you an idea of the rage going on in the room. >> reporter: peglo, who has studied the interview video says there's one thing she can't forget. near the end he realized alex's breathing had become labored, that the woman he said he loved was dying. >> reporter: didn't get help, didn't call an ambulance, didn't occur to him. instead, he hit her until she died to put her out of her misery, he said. must have seemed almost impossible. how could she be murdered? >> absolutely. disbelief, shock. you don't go away to college and, um, suffer that. you just don't. >> reporter: clayton whittemore charged with second degree murder. he pleaded not guilty because he had an explanation. his attorneys would reseal it at trial. coming up, could anything explain such violence? the verdict when we continue. [ coughing and sneezing ] cold season is back. bounce back fast with alka seltzer plus. with 25% more concentrated power. alka-seltzer plus. ♪ oh, what a relief it is ♪ so fast! also try for cough, mucus & congestion. that's a nice truck. yeah, it's the chevy silverado. check out this multi-flex tailgate. multi-flex, huh? wow. it becomes a step. mom, dad's flexing again. that's not all. you can extend the bed for longer stuff. is he still... still flexing. that's right! and, it becomes a workspace... you can put your laptop here. i'm sending an imaginay email. hey dad, dinner! hey! look who stopped by daddy's office. wait, you work here? the chevy silverado with the available multi-flex tailgate. find new flexibility. find new roads. chevrolet. ♪ after a night like this, find new flexibility. find new roads. crest has you covered. crest, the official toothpaste of santa. follow us @crest to celebrate the 12 days of crest smiles. it wasn't until the spring of 2014, almost two years after alex kogut died that clayton whittemore went on trial. although he told the cops he had beaten his girlfriend to death, he entered a plea of not guilty. prosecutors had a powerful case against him and they knew it. the gruesome images, even his words. >> reporter: he was a ticking time bomb, prosecutors argued a killer years in the making. how does this young man go from star athlete, popular, college student to what some would call a monster? >> you know, our theory that night was his anger was building, building and perhaps fuel bide alcohol. >> reporter: prosecutors tried to show that clayton whittemore already established a pattern of violence. called ex-girlfriend to testify about a scary episode. >> we were arguing in a parking lot, he choked me. i locked him out of his car to cool down and he did. >> reporter: but that one was serious? >> yeah, it was scary. >> reporter: hunter played hockey on the college prep team in florida. hunter, too, had a scary experience. it happened after clayton drank half dozen beers. the one team he saw his teammate drink. >> he walks in the kitchen and grab as knife and looked like he was possessed. he took a step towards us and our host mom saw what was happening and said, clayton put the knife down. >> reporter: the defense attorneys didn't deny he killed alex and didn't deny this was years in the making. they say he was guilty of the lesser charge of manslaughter. why? because he was under extreme emotional disturbance because clayton whittemore is a victim himself. >> reporter: that's clayton talking to the 911 dispatcher hours after the murder. he's talking about his dad. telling the dispatcher his dad abused him and his family for years. >> reporter: the cops in the interview room asked him how he felt about his dad now. >> reporter: in the minutes before he was arrested, clayton wrote a bizarre apology to alex and the koguts. sorry to you, he wrote. nothing will ever fix or undo what i did. i became my father. clayton's sister took the story. their father did not respond. there are no claims against him. scott admitted as a former marine, he may have been rough. because of that abuse, they concluded clayton was suffering the extreme emotional disturbance and snapped in the dorm room . the prosecution begged to differ. >> it's sad and tragic. we never discounted or denied his past but that doesn't excuse what he did. >> reporter: three weeks after the trial began, the case went to the jury. the verdict was swift. guilty of second degree murder. >> i felt this overwhelming sense of relief that the truth came out and that there was -- there was finally a verdict. it was the right verdict. >> reporter: alex's mom did not attend the trial but followed it closely and tweeted. after the verdict, she tweeted "justice for my beautiful baby." did you talk to her? >> uh-huh. >> what did she say? >> it was a private conversation between two moms. there were tears, of course. doesn't bring back alex. it doesn't. >> reporter: clayton whittemore was sentenced to 25 years to life. now, among those who know the story of alex kogut's life and death, there's a new awareness of the vulnerability and challenges of young love, especially because, prosecutors say, there was evidence to show clayton had a history of threatening alex. he left angry voice mails on her phone. >> there were almost 30 voice mails that she saved from him. they were all of the aggressive controlling. we have them at trial. >> reporter: voicemails were not admitted in court, but they read an excerpt. >> i'll kill you next time i see you. you're a slut and a skang, so don't call me. i'm sick -- i'm sick of you and i left a lot of words out. >> when you add in the expletives, it's really hard to hear. >> these were voicemails that really were scary. >> reporter: those close to alex and her family say they never knew about the voicemails or knew there were red flags from clayton whittemore. >> that's why it's out of the blue. never saw that coming. >> nothing. totally caught me off guard. >> reporter: perhaps there's a lesson to be learned. ask questions, know what's happening, even if there are no warning signs. >> even if they may not want to be talking about it, ask those questions. >> reporter: after alex died, sandra whitney and her family started a charity to campaign against dating violence. purple symbolizes the fight against domestic violence and also alex kogut's favorite color. she came up with it as she comforted alex's former teammates. >> i said paint your pinkies purple and this is for alex. you have more strength in your pinky than the worst thing that could have happened. >> reporter: still purple ribbons in alex's home town. still a memorial to honor students that have died. the college, that itself has had to heal and has since opened an awareness to dating violence. and there are still those, like page whitney, that will never let the memory of a gracious, joyous young spirit fade away. >> for the rest of my life, whenever i see purple, i will think of her, whenever i hear a story of any type of domestic violence i will think of her and i will never stop telling her story. >> that's all for now. >> i'm craig melvin. >> and i'm natalie morales. >> and this is dateline. >> i couldn't comprehend what was happening. i couldn't sleep. losing my husband. it's an image that is never gonna go away. >> a father out for a walk with his son. >> i heard shots. very loud shots. >> the child survives, the father doesn't. >> all he was asking was, "honey, tell me how's the baby? is the baby okay? " >> it was an execution? >> yes. >> the killers never caught. >> we're waiting for a