hamas hitting a tent camp, killing dozens of palestinians. prime minister netanyahu calling it a tragic incident. the global outrage tonight. the urgent search for survivors in papua-new guinea. a catastrophic landslide hitting in the middle of the night. more than 2,000 feared buried alive. the horrifying rampage inside a u.s. movie theater. four girls stabbed but surviving. three of them sisters. their mother speaking out. the mid-air scare for boxer mike tyson. the medical emergency he suffered on a cross-country flight. remembering nba hall of famer bill walton. he was a legend on the basketball court and in the broadcast booth. and on this memorial day a final salute to a pearl harbor hero more than 80 years in the making. >> announcer: this is nbc "nightly news" with lester holt. and good evening on this memorial day. i'm tom llamas in for lester. we begin tonight with the severe storms slamming the east coast. just as millions of americans are returning home from their holiday travels. more than 60 reported tornadoes ripping across the central u.s. this weekend alone. major damage from texas to arkansas to kentucky. the death toll rising to at least 23. and tonight we're tracking the threat as it moves east. 62 million people under severe risk from texas all the way to new york. severe thunderstorm watches are in effect for major cities including philly and new york city. and tornado watches in the mid-atlantic including for washington, d.c. we'll check in on travel in just a moment, but first we start off with priscilla thompson in the storm zone in texas. >> we're in it. >> oh, there it is. go, go, go. >> reporter: tonight, the vicious storms that battered the heartland barreling east. drenching new york city and parts of the coast. after tearing a cross-country path of destruction. >> it's terrible. terrible. terrible. it won't ever be the same. >> reporter: more than 20 people have died in memorial day weekend storms after upwards of 60 reported tornadoes across a dozen states. >> when it hit, the floors, you could just feel the floors just wave kind of up and down. >> reporter: in kentucky this massive twister touched down in eddyville. the damage in nearby dawson springs where a tornado seemingly cut clear across town, shredding entire homes. our kathy park is there. >> the dangerous storms blew in overnight, catching many people off guard, including one couple in their 90s. we're told they were on this bed as the extreme winds tore their house apart. incredibly, they survived. >> reporter: in hard-hit arkansas streets littered with debris. winds so powerful they ripped off the front of this dollar store. here in valley view, texas officials now say 125 people were trapped in this rubble after the gas station they were sheltering in crumbled. >> it felt like i was living in a nightmare. >> reporter: among them, elizabeth hernandez, who filmed this terrifying video. >> what was the scariest moment? >> when it actually hit and like we could feel the wind of it. it felt like we were outside. i was just waiting for us to be either lifted up or something to smash on us. >> reporter: less than a mile up the road, monica vasquez was in a closet with her husband and five children, the youngest just 3 years old. >> what was going through your mind? >> that i don't want to die. >> incredible that family survived. priscilla joins us now from hard-hit valley view, texas just north of dallas. priscilla, a community that has lost so much and still so many injured. >> reporter: yeah, tom. so many injured. and when you see this devastation, you understand how. i am standing on the foundation of this home. that house now over there. the entire second floor gone. as across the country communities like this one are continuing to clean up. tom? >> all right. priscilla thompson leading us off tonight. priscilla, thank you. and that severe weather hitting just as memorial day travel is shattering records. our priya sridhar is at atlanta's hartsfield-jackson airport where there was a ground stop earlier today. priya, how's it looking now? >> reporter: well, tom, the record number of americans who traveled this holiday weekend are trying to make their way home as that destructive storm system heads east. the flightaware misery map showing delays and cancellations along the east coast. as of now more than 5,000 delays so far. here in atlanta long lines as travelers try to make their way home. the tsa says it broke a record on friday with nearly 3 million screened. meantime, aaa predicted the biggest number of road trippers ever, some 38 million driving this holiday weekend. experts say the memorial day numbers indicate a strong summer travel season ahead. tom? >> all right, priya, we thank you for that. now to another major story we're following tonight. the search for suspects after a former star of "general hospital" was fatally shot right on the street. his family telling our morgan chesky he died protecting a co-worker. >> reporter: tonight, a stunning murder in downtown los angeles of soap opera star johnny wactor. police say they're searching for three suspects after the 37-year-old was fatally shot early saturday as he encountered thieves trying to steal his car's catalytic converter. wactor's family tells nbc news he was leaving a job at a downtown bar later than usual, walking with a co-worker when he noticed a man near his car. wactor's mother said her son asked if he was about to be towed. but when a man looked up wearing a mask wactor shielded his co-worker with his body and that suspect shot him. >> it's just such a senseless thing. >> reporter: scarlett wactor spoke to us by phone. >> i hope that they will catch whoever did it. i hope that there will be some kind of justice for johnny. >> i want you to tell me. >> reporter: wactor was best known for his role as brando corbin on "general hospital," appearing in 164 episodes of the popular daytime soap. wactor's colleagues remembering a dear friend. "general hospital" posting "he was truly one of a kind." his tv wife writing, "my heart is so utterly broken. johnny was the absolute best." >> he lived life to the fullest. he always tried to be positive for everybody. he was a light in a dark room. and he will be very missed. >> and morgan joins us live from los angeles tonight. morgan, this type of theft targeting catalytic converters, it's grown so bad multiple states are trying to crack down? >> reporter: yeah, tom, that's right. and it's the precious metals inside these converters that thieves are really after here. that's why more than a dozen states have enacted laws not only cracking down on the theft here but also resale on the black market. meanwhile, tonight lapd has yet to release any description of those three suspects. tom? >> all right, morgan chesky for us. we want to head to the middle east now. an israeli airstrike hitting a tent camp leaving dozens of palestinians dead. prime minister benjamin netanyahu calling it a, quote, tragic incident. raf sanchez has more. >> reporter: tonight grief and anger across southern gaza after an israeli airstrike hit a camp for displaced people in rafah, sending flames ripping through tents and killing at least 45 people, many of them women and children according to the emergency services in hamas-run gaza. the idf said it hit a hamas compound and killed two commanders. prime minister benjamin netanyahu today calling it a tragic incident and promising an investigation. the white house calling the images heartbreaking, saying israel has the right to pursue hamas but must protect civilians. "children were in the streets screaming," this woman says. meanwhile, u.s. military vessels delivering aid from an american-built temporary pier broke free from their moorings in heavy seas. this is one of the small military boats that washed up on the beach here in israel. there's two more about 20 miles down the coast in gaza. u.s. central command hoping to get this one free sometime soon. back in rafah families already displaced several times are picking through charred remains of their tents, salvaging what they can before moving on again in search of safety. and egypt today says one of its soldiers was killed in an unusual cross-border gunfight with israeli troops. both sides say they're investigating. tom? >> raf sanchez in tel aviv tonight. raf, thank you for that. we're also tracking the urgent search for survivors after a devastating landslide in papua-new guinea. the government fearing more than 2,000 people were buried alive. meagan fitzgerald joins us now. and meagan, what do we know at this hour? >> reporter: tom, that desperate mission under way and by the most basic means. people are using poles and sticks after that mudslide was triggered in the middle of the night while people were asleep. now, the u.n. is putting those trapped beneath the rubble at around 670. but the government fears that that number is much higher. meanwhile, we know roads have been cut off, making it that much more difficult to try and bring in heavy machinery. fewer than ten people have been recovered as people on the ground are saying that it's a race against time to try and get these survivors. tom? >> all right. we hope those rescue teams can get in. meagan, we thank you for that. and a high-stakes visit is under way in taiwan. a delegation of u.s. lawmakers meeting with the country's new president and pledging weapons to defend against the threat from china. ryan nobles is the only broadcast network reporter traveling with the delegation and has more. >> reporter: tonight, the message from washington to taipei is crystal clear. [ speaking in a global language ] "we love taiwan." the first words from house foreign affairs chairman mike mccaul to the island's new president, lai ching-te. taiwan is self-governed, but china claims it as part of its territory. china reacted to lai's swearing in by moving warships and fighter jets close to taiwan's shores and warned american leaders not to go to taiwan. >> but you came anyway. why? >> because we support taiwan. we support freedom and democracy against dictatorships like the one that's very close to where we're sitting right now. people's republic of china. >> reporter: china's aggressive posture has american leaders worried. the u.s. is investing billions of dollars to fortify taiwan's military with the goal of deterring an attack. but inside this flower market in downtown taipei there are little signs of anxiety, with most shoppers telling us that they are happy with the status quo. >> china had military exercises this week. does that ever worry you? >> not much. because that's almost become a part of our daily life. >> reporter: and the world's economy is reliant on taiwan. 90% of the world's advanced semiconductors are produced here. a supply chain that would be interrupted if china were to attack. tom? >> those chips are so critical. all right, ryan, we thank you for that. and back here at home some sad news tonight from the sports world. hall of fame basketball player bill walton, who later became a beloved broadcaster, has died after a battle with cancer. jesse kirsch now on his legacy on and off the court. >> reporter: on the court and on the mic -- >> dust it off. >> reporter: -- bill walton was a towering figure in the world of basketball. a 6'11" california kid, walton played center for ucla coaching legend john wooden. the dynamic big man helped the bruins win back-to-back national championships in 1972 and 1973. both teams were undefeated. while in college he also made headlines for an arrest while protesting the vietnam war. reportedly, he was bailed out of jail by his coach. >> walton on the lob. >> reporter: later in the nba walton won championships for portland and boston. undeterred by a speech impediment, the hall of famer kept the highlights coming as a broadcaster. >> strip down right here. >> bill is taking his shirt off. >> reporter: his best moments arguably had nothing to do with the game. >> take a bite out of it while it's lit. >> while it's lit? >> i'm kidding. >> reporter: the nba says the basketball legend died today surrounded by family, following a prolonged cancer battle. >> it takes talent to get to the top. it takes character to stay there. >> reporter: bill walton was 71. jesse kirsch, nbc news. and in just 60 seconds, the mid-air medical emergency for boxer mike tyson. what happened on his flight? and the stabbing spree in a movie theater. four girls surviving. their mother speaking out. four girls surviving. their mother speaking out. ♪tell me why♪ because it stinks. ♪have you tried downy rinse and refresh♪ it helps remove odors 3x better than detergent alone. it worked guys! ♪yeahhhh♪ downy rinse and refresh. when dry eye symptoms keep... coming... back... inflammation might be to blame. over-the-counter eye drops can provide temporary relief. xiidra can provide lasting relief. it targets inflammation that can cause dry eye disease. xiidra? no-o-o! xiidra treats the signs and symptoms of dry eye disease. don't use if allergic to xiidra. common side effects include eye irritation, discomfort or blurred vision when applied, and unusual taste sensation. why wait? ask your doctor about a 90-day prescription and pay as little as $0. xiidra. (grunt) i am obsessed with olay's retinol body wash. with olay retinol body wash, 95% of women had visibly renewed skin. it makes my skin feel so smooth and moisturized. see the difference with olay. we're back now with a medical scare for boxing legend mike we're back now with a medical scare for boxing legend mike tyson. paramedics had to help the former heavyweight champ on a flight from miami to los angeles on sunday. his team tells nbc news he became nauseous and dizzy from an ulcer flare-up but he's doing great now. the 57-year-old is set to fight youtuber jake paul on july 20th. now to a terrifying stabbing rampage inside a movie theater. the mother of three of the victims speaking out. stephanie gosk has more. >> reporter: her daughters were at the movies on saturday night when lisa dembowski got the call. >> i needed to get to the amc movie theater right away because they had been stabbed. >> reporter: according to authorities, jared ravizza attacked dembowski's three daughters and a friend with a knife in their seats, unprovoked. >> my oldest was leaned over to get something. he got her in the back. and then my other daughter in the top chest. and then my last daughter across her arm. >> reporter: the girls, ages 9 to 17, sustained non-life-threatening injuries. an hour later police say 26-year-old ravizza, who lives on the wealthy island of martha's vineyard, went to a rest stop mcdonald's, stabbing one employee in the drive-thru and another inside. according to authorities, ravizza fled in his black porsche suv, which he crashed. he was then arrested. multiple law enforcement sources tell nbc boston the stabbings may be connected to a death investigation in connecticut. so far ravizza faces multiple charges including assault with intent to murder. dembowski says her daughters are physically okay but definitely rattled. >> i think it's a pretty sick individual to harm children. >> reporter: ravizza is expected in court tomorrow. stephanie gosk, nbc news. all right. up next, a new warning about fake nude images targeting kids in high school made by their classmates. stay with us.. i got the power of 3. i lowered my a1c, cv risk, and lost some weight. in studies, the majority of people reached an a1c under 7 and maintained it. i'm under 7. ozempic® lowers the risk of major cardiovascular events such as stroke, heart attack, or death in adults also with known heart disease. i'm lowering my risk. adults lost up to 14 pounds. i lost some weight. ozempic® isn't for people with type 1 diabetes. don't share needles or pens, or reuse needles. don't take ozempic® if you or your family ever had medullary thyroid cancer, or have multiple endocrine neoplasia syndrome type 2, or if allergic to it. stop ozempic® and get medical help right away if you get a lump or swelling in your neck, severe stomach pain, or an allergic reaction. serious side effects may include pancreatitis. gallbladder problems may occur. tell your provider about vision problems or changes. taking ozempic® with a sulfonylurea or insulin may increase low blood sugar risk. side effects like nausea, vomiting, and diarrhea may lead to dehydration, which may worsen kidney problems. living with type 2 diabetes? ask about the power of 3 with ozempic®. so, i didn't think i needed swiffer. until... i saw how easily it picked up my hair every time i dried it. it only takes a minute. look at that! the heavy duty cloths are extra thick for amazing trap and lock. even for his hair. wow! and for dust i love my heavy duty duster. the fluffy fibers trap dust on contact up high and all around without having to lift a thing. i'm so hooked! you'll love swiffer or your money back! uhhh. katie! i knew i'd find you here. i know, it's wild. i'm you from the future! anyway our doctor figured it out. all that constipation with belly pain that keeps coming back, it's ibs—c. she said linzess could help you get ahead of it. whatta you say? yess! get ahead of your ibs—c with linzess. linzess is not a laxative. it's a once—daily pill that helps you get ahead of your symptoms. it's proven to help you have more frequent and complete bowel movements. and helps relieve overall abdominal symptoms... belly pain, discomfort, and bloating. do not give linzess to children less than two. it may harm them. do not take linzess if you have a bowel blockage. get immediate help if you develop unusual or severe stomach pain, especially with bloody or black stools. the most common side effect is diarrhea, sometimes severe. if it's severe, stop taking linzess and call your doctor right away. these aren't all the side effects. imagine...what could relief from ibs—c mean for you? talk to your doctor and say yess to linzess. learn how abbvie and ironwood could help you save. all right. we are back now with our series "ai revolution." and a warning to parents about a disturbing trend. the rise of fake nude images targeting teenagers and made by other teens. here's valerie castro. >> reporter: 15-year-old stevie heider's memory of prom last year is no longer a happy one. >> i can't look at the photo anymore. >> reporter: stevie's family says she was one of dozens of students at richmond burton high school in illinois targeted by classmates who police say used artificial intelligence to create fake nudes. in stevie's case taking her face from this prom photo and swapping it onto a sexually explicit image. students then texting the images around school. >> i asked them if they could just pull up the photo. and it was just -- immediately felt like nauseous and gross. yeah, it's my face there but that's not my body. >> reporter: the school is saying it is unable to discuss an ongoing investigation involving students. stevie's mother, stephanie, furious. >> we shouldn't have to teach our girls to have to hide their prom photos. that's just ridiculous. >> reporter: but increasingly, young people, usually girls, are at risk from their own peers using so-called nudification apps with cases like stevie's popping up all over the country. the national center for missing and exploited children says it's seeing a spike in ai-related calls to its tip line. >> is this a situation where the law is trying to play catch-up to this technology? >> i think so. and i think that's something that we oftentimes see, where technology moves so fast across all sectors of tech. the laws and legislation are continually having to catch up. >> reporter: the law surrounding these ai-generated pictures is often murky because they aren't considered real intimate images. existing laws don't necessarily apply to them. though a few states have now passed legislation specifically to combat sexually explicit ai images of minors. and the fbi says child sexual abuse material created with content manipulation technologies to include generative artificial intelligence is illegal. >> you want to see criminal charges? >> absolutely. there absolutely should be criminal charges. >> reporter: some parenting advocates say what's needed is more focus on prevention and teaching kids how to use ai tools ethically. in stevie's case two minors were arrested according to the state's attorney's office, charged with a total of 34 counts of child pornography. the impact on stevie ongoing. worried about what to do with this year's prom pictures. >> i'm definitely nervous for posting that. i just hope those don't end up on the news too. >> reporter: stevie trying to enjoy the authentic parts of her teenage years while living with a very real artificially generated threat. valerie castro, nbc news, richmond, illinois. and up next, an emotional farewell for a war hero and the breakthrough that made it possible. made it possible. but i manage it well ♪ ♪ jardiance! ♪ ♪ it's a little pill with a big story to tell ♪ ♪ i take once-daily jardiance ♪ ♪ at each day's start! ♪ ♪ as time went on it was easy to see ♪ ♪ i'm lowering my a1c! ♪ jardiance works twenty-four seven in your body to flush out some sugar. and for adults with type 2 diabetes and known heart disease, jardiance can lower the risk of cardiovascular death, too. serious side effects may include ketoacidosis that may be fatal, dehydration that can lead to sudden worsening of kidney function, and genital yeast or urinary tract infections. a rare, life-threatening bacterial infection in the skin of the perineum could occur. stop jardiance and call your doctor right away if you have symptoms of this infection ketoacidosis, or an allergic reaction. you may have an increased risk for lower limb loss. call your doctor right away if you have symptoms of infection in your legs or feet. taking jardiance with a sulfonylurea or insulin may cause low blood sugar. ♪ jardiance is really swell ♪ ♪ the little pill ♪ ♪ with a big story to tell! ♪ summer's on its way... and wayfair's big memorial day clearance is here now! it's the talk of the town. right now through may 28th, get up to 70% off everything home. save on finds for indoors and out. plus, score surprise flash deals that'll make your day. and get it all with fast shipping straight to your door. save up to 70% off wayfair's memorial day clearance now through may 28th, and kickstart your summer with savings! ♪ wayfair every style, every home ♪ mike had a heart attack a year ago. but he's still living in the red. with a very high risk of another attack. with his risk factors his recommended ldl-c level should be below 55. find out if you're living in the red. learn how to get a free ldl-c test. liberty mutual customized my car insurance and i saved hundreds. that's great. i know, i've bee telling everyone. baby: liberty. oh! baby: liberty. how many people did you tell? only pay for what you need. jingle: ♪ liberty. liberty. liberty. ♪ baby: ♪ liberty. ♪ breathing claritin clear is like... [♪♪] feeling the breeze instead of feeling congested. [♪♪] fast relief of allergies with nasal congestion, so you can breathe better. claritin plus decongestant. live claritin clear®. wanna know a secret? more than just my armpits stink. facts. that's why i use secret whole body deodorant for clinically proven odor protection everywhere. so i smell great all day, all hike, and all night. secret whole body deodorant. struggling with bowel leakage? it's more common than you think. my bowel incontinence left me feeling embarrassed and isolated for years. but that all changed when a physician specialist told me about axonics therapy. it's given me real, long-lasting relief from my symptoms. visit findrealrelief.com to get help arranging an appointment with an expert physician that can determine if axonics therapy is right for you. results and experiences may vary. get back to doing the things you love! our behavior will tell you what happened. plus, we're marking 60 days into the olympics with brie. athletes and coaches president biden marking memorial day at arlington national cemetery today, where recently the family of a pearl harbor hero gathered for a long-awaited final salute. here's courtney kube. >> reporter: growing up in california in the 1920s, starring winfield and his siblings were inseparable. >> he always looked out for his sisters, older, younger. they were all very close. >> reporter: adam morrill's grandmother was starring's sister. she always used to brag about her baby brother the war hero. >> we were always told stories when we were kids. >> reporter: starring enlisted in the navy in 1940 and was assigned to the "uss oklahoma." on leave he married his high school sweetheart before heading to pearl harbor. six weeks later she would be a widow. on december 7th, 1941 during a surprise attack, japanese torpedoes sunk the "oklahoma," killing 429 u.s. sailors and marines and leaving 388 listed as unaccounted for including starring. >> he was missing in action, presumed dead. >> reporter: two years later the navy righted the ship and the remains of those who could not be identified were buried together. then in 2015, armed with new advances in dna identification, the military disinterred the remains, beginning the painstaking effort to identify the fallen servicemembers. >> we have an obligation as a nation to not leave them behind. and so this is that fulfillment of that promise. >> reporter: returning the remains of 361 men to their families. radioman third class starring winfield was one of them. receiving full honors as he was finally laid to rest at arlington national cemetery earlier this month. >> today is more about a celebration of him. he's finally getting this lasting monument and a place of just honor. ♪ >> reporter: a final salute for an american hero. a poignant farewell for his proud family. courtney kube, nbc news, arlington national cemetery. and with that we join all of you in honoring those who died to protect our freedom on this memorial day. that's "nightly news" for this monday. i'm tom llamas. thank you so much for watching. have a great night. watchin. have a great night. arrested in the south bay, accused of some unnerving behavior for part of it caught on camera. we're going to show you what happened. plus california is starting to see an uptick in covid cases. what's driving the summer spike? why are some people. tonight we're getting some insight from an expert.