cancer. the science is similar to the covid-19 vaccine. all that and more coming up with lester holt. tonight, no charges against the ohio police officers who killed jayland walker a grand jury deciding not to indict the eight officers who fired dozens of rounds at the 25-year-old black motorist last june the state attorney general saying the officers thought walker was reaching for a gun during a chase. will it ignite new protests breaking news in kansas city. a homeowner charged with two felony counts after he shot a black teenager who rang his doorbell mistakenly. the prosecutor now saying there was a racial component in the case growing outrage by u.s. allies after the leak by a national guardsman of those top secret documents, and what they reveal about washington's china concerns a string of massive and worrying chemical explosions across america

the new calls for tougher regulations. > the mysterery at sea. what happened to three experienced american sailors who disappeared without a trace off the coast of mexico almost two weeks ago? a new treatment for melanoma brings promising results. rates of recurrence and death down dramatically and ten years after the boston marathon bombing, how their injuries forged a bond that has withstood the test of time, inspiring america. >> announcer: this is nbc "nightly news" with lester holt good evening and welcome. an akron, ohio grand jury charging decision in the police shooting death of jayland walker has that city on nervous edge tonight. the grand jury declining to indict eight police officers who fired some 46 bullets into walker, killing him. it happened at the end of a chaotic chase last summer, much of it caught on police dash and body cams walker was black seven of the officers

are white. ohio attorney general dave yost today noting the sheer number of shots is one of the things that made it hard to watch but said evidence showed walker shot first the officers, he says, were legally justified. though walker was unarmed at the moment police opened fire the shooting set off protests and unrest in the streets last june. looking toward tonight, akron's mayor saying he has faith in his community. correspondent jesse kirsch has late details. >> reporter: tonight ohio's attorney general announcing the eight akron police officers who shot jayland walker more than 40 times will face no state criminal charges for killing the 25-year-old black man. >> the grand jury concluded that the officers were legally justified in their use of force >> reporter: walker's family outraged by the decision >> i wish you could have been in the home about 4:30 p.m. when i broke the news to the family i wish you could have

heard and felt and seen the screams >> reporter: authorities say last june police attempted a traffic stop before walker fled in his vehicle, firing at least once at officers before taking off on foot in a ski mask authorities say officers twice tried stopping walker with a taser. >> mr. walker then reached for his waistband in what several officers described as a cross-draw motion, planted his foot, and turned toward the officers while raising his hand only then did the officers fire. >> reporter: officers firing 94 shots in less than seven seconds. walker was hit roughly 46 times >> it is critical to remember that mr. walker had fired on the police and that he shot first >> reporter: the officers have not been publicly identified. the release of their body cam footage last summer sparked large protests here. a special grand jury

reviewed evidence for more than a week, according to the attorney general seven of the nine special grand jurors would have needed to find sufficient evidence to issue an indictment >> by all accounts this was a good man, a good person with no prior criminal record. so he was not acting himself. >> reporter: tonight the city of akron calling for peace. >> we will protect our citizens' right to assemble, demonstrate and petition this government, but to do so peacefully. >> so jesse, how is the community there reacting >> reporter: yeah, tonight some buildings in akron boarded up. you can see downtown is largely quiet and peaceful but already for tomorrow the city's public schools will be closed lester >> all right jesse, thank you breaking news from kansas city, missouri tonight. an 85-year-old white man has just been charged in the shooting of a black teenager who rang his doorbell by mistake. it follows a weekend of protests over the shooting maggie vespa joins us live now maggie, what charges does he face

>> reporter: so lester, prosecutors in clay county announcing 85-year-old andrew lester faces one count of assault in the first degree and one count of armed criminal action. and they add there was a, quote, racial component in the shooting of a teenage boy who family says made a simple mistake and went to the wrong home tonight, after days of protests demanding justice the kansas city homeowner who family say shot 16-year-old ralph yarl twice for ringing the wrong doorbell faces criminal charges >> i can assure you that the criminal justice system is working and will continue to work as with any serious case, we approached this one in an objective, impartial manner >> he has the times where he's like why, i did nothing wrong, why. >> reporter: dr. faith spoonmore says her nephew was trying to pick up his younger twin brothers from a friend's house thursday night when he mistakenly went to the wrong home

civil rights attorney lee merritt says ralph rang the doorbell and waited >> and he was confronted by a man who told him don't come back around here. and then he immediately fired his weapon, striking mr. yarl in the head he went to the ground, and then he was shot a second time. >> reporter: merritt adding ralph was able to run for help after being shot and says ralph knocked on multiple doors before a neighbor answered and ordered the boy to lie on the ground and put his hands up >> ralph decided to comply and essentially lose consciousness after that, which is what allowed him to get medical treatment. >> reporter: the shooting sparking outrage on social media. hollywood heavyweights like viola davis and halle berry demanding charges. fueling that fury, police taking the homeowner into custody and 24 hours later, they say, releasing them without charges prosecutors now say the charges followed a thorough review of the case police put together >> as the prosecutor of clay county i can tell you there was a racial component to the case >> reporter: they add the felony charges

filed against andrew lester carry a potential sentence of up to life in prison a warrant issued immediately for the 85-year-old's arrest >> it's been my goal from the very beginning to get justice for the child involved in the case >> reporter: tonight the family says ralph, a marching band standout with dreams of studying chemical engineering, is healing. >> he's alive. i think that's the biggest message that i want people to remember, is that he is alive >> reporter: prosecutors in kansas city said today they also did not pursue hate crime charges because in this case under missouri law they say those charges would have come with a shorter sentence and then also new tonight, ralph yarl's family attorney says the teen today spoke to president biden, who invited him to the white house and told him we are all waiting to see justice in your case lester >> all right, maggie vespa. thank you. new calls tonight both here and from u.s. allies for greater controls on america's top secrets. four days after the arrest of that 21-year-old national guardsman charged with

leaking intelligence documents. andrea mitchell has the latest >> reporter: as the british defense minister was being honored at the pentagon today, behind the scenes sharp criticism from many u.s. allies whose officials tell nbc news they are outraged by what they call america's careless handling of top secrets. despite these comments from secretary of state blinken. >> what i've heard so far at least is an appreciation for the steps that we're taking, and it's not affected our cooperation. >> reporter: after thursday's arrest of national guard airman jack teixeira, allies are asking how the enlisted 21-year-old was able to print classified documents undetected and apparently photograph them on his kitchen counter as first noted by the "new york times. how does a massachusetts guardsman at otis air force base in cape cod not only have the access but they don't

have enough secure procedures to know that he's taking stuff home >> well, andrea, this is outrageous. there's no doubt about that this is a terrible leak this can have consequences for our ability to gather information, for our sources to trust us, for our allies to trust us >> reporter: among the leaked secrets, a pentagon assessment that taiwan cannot defend itself against chinese missile launches according to a document obtained by the "washington post" and not verified by nbc news sparking a call for the biden administration to speed up u.s. arms sales to taiwan. from a top republican who just met taiwan's president. >> when i meet president tsai, her first question is when am i going to get my weapons. >> reporter: the "washington post" also reporting the u.s. knew of up to four additional chinese spy balloons beyond the one that flew across the u.s. the pentagon is declining comment. another "post" document details china successfully testing a hypersonic missile that possessed a high probability of being able to evade u.s. air defenses >> and andrea, there's

also a major headline from russia, where a top u.s. diplomat was allowed to visit an imprisoned american "wall street journal" reporter for the first time >> exactly right, lester finally today russia permitted the u.s. ambassador to visit evan gershkovich, in prison almost three weeks after his arrest on false espionage charges. the ambassador reported he appeared to be in good health tomorrow he will be in court behind closed doors to appeal the charges. and in an alarming example of russia's crackdown today they sentenced "washington post" contributor and putin critic vladimir kara-murza to an unprecedented 25-year sentence for criticizing the war in ukraine. lester >> andrea mitchell, thank you. tonight, deepening intrigue in the growing tensions between the u.s. and china. two men arrested on charges they ran a secret police station in new york city on behalf of the chinese government gabe gutierrez joins us gabe, this is allegedly part of a global pattern >> reporter: yes, lester the department of justice says that a

secret police outpost in that nondescript office building behind me was one of more than 100 chinese police operations around the world, part of a massive effort to suppress criticism of china's communist government now, the two men, both u.s. citizens, were arrested on federal charges, one allegedly tracking down a pro-democracy activist in california. and separately more than three dozen officers with china's national police force have been charged with using social media to harass dissidents living in the u.s. now, china's embassy has previously said that these were not police stations but rather volunteer-run facilities meant to help chinese nationals. no comment today from the chinese embassy. lester >> gabe gutierrez, thank you. there's growing concern following a series of massive chemical fires and toxic spills nationwide families who live in impacted communities fear there could be long-term health problems here's tom costello. >> reporter: from that massive fire in georgia to a chemical spill near

philadelphia, the train derailment in east palestine and the plastics fire in richmond, indiana, fear of the unknown is most terrifying. the epa finding hydrogen cyanide, benzene, chlorine and carbon monoxide. >> it's hard for me to breathe. my lungs are hurting i have an extremely bad headache >> reporter: lynn childers already had emphysema. he lives 5 1/2 miles from the richmond fire and was outside gardening with his great-grandchild >> and this black it looked like soot or something falling from the sky. >> reporter: cherese munion lives in east palestine. >> i'm concerned with myself but i want to make sure that my kids are going to be okay >> reporter: a coalition of groups working to track and prevent chemical disasters estimates there's a chemical fire, explosion, or toxic release every other day in this country. >> that is just simply too much you can't smell cancer on your skin, right? so these chemicals can do harm, either immediately or over a long period of time.

>> reporter: the coalition wants stronger epa regulations on hazmat storage, switching to safer alternatives, and informing communities and firefighters of the toxins in their back yards. lung experts warn even minimal exposure to some toxins can do lasting damage >> the effects can last for some time and how long, could be weeks, could be months, could be years. >> reporter: lynn childers is most concerned for his 4-year-old great grandchild >> my time probably is short in this life but my grandchildren and my great grandchildren, what's the long-term health effects that's going to be on her >> reporter: the chemical concerns come as non-smoking lung cancer rates are rising in the u.s. researchers blame exposure to air pollution and toxins lester >> all right tom costello, thank you. in 60 seconds the desperate search at sea. what happened to three americans, all experienced sailors who set off from mexico for san diego the deepening mystery, next

all right. we're back now with that mystery at sea and the massive search for three american sailors who vanished without a trace. mimiguel almagueuer reports.s. >> repeporter: tononight in t the waters s off mexico a d desperate seararch for thrhree amamericans fefeared lost t at sea husband anand wife frarank and kekerry o'brieien and theieir friend w william grososs have nowow been missing g 13 days. alall are said to be experienced sailors. the o'briens are even licensed coast guard captains >> hopefully somebody sees them and gets them to make contact or relays the messages out there. >> reporter: headed to san diego on their 44-foot vessel "oceanbound," the sailors were last heard from april 4th, when they shoved off from the mexican resort city of mazatlan, planning to arrive in cabo san lucas two days later for supplies the coast guard says there's no record of them arriving or of a mayday call.

>> the information that we have is that there was not an emergency beacon on board. >> reporter: the trio may have faced 20-foot waves and 30-knot winds. tonight the mexican navy and the u.s. coast guard says rescue teams are scouring a 2,500-square-mile search grid along the baja peninsula almost twice the size of rhode island. while the crew did set sail from a do not travel zone, authorities tell family members they don't believe the boat would be a target for cartels. >> we're pleading for anyone out there to be on the lookout >> reporter: tonight the desperate search and the deepening mystery at sea miguel almaguer, nbc news up next tonight, a promising new treatment for the deadliest form of skin cancer

there's new promise tonight in the battle against the most deadly form of skin cancer. it's a treatment that uses new vaccine technology and your own immune system to stop the disease kristen dahlgren reports. >> reporter: tonight, what may be a watershed moment for fighting cancer. >> the data were pretty darn impressive >> reporter: in a stage 2 clinical trial researchers like dr. jeffrey webber found adding an mrna cancer vaccine to standard treatment reduced ththe chances for melanoma recurrence or death by 44%. research on the vaccine was started before an mrna vaccine was used for covid and it works similarly. doctors use a

blueprint from a patient's individual tumor to encode a personalized vaccine >> so basically turning your own immune system against the cancer >> that is absolutely correct. we're going to generate killer cells that are going to seek out and find the tumor and get rid of it. >> reporter: in 2019 gary keblish got the devastating diagnosis, advanced melanoma. the deadliest form of skin cancer. >> i feel that i probably would have been one of those statistics had i not been involved in the clinical trial >> reporter: more than three years later gary is still cancer-free >> taking this vaccine has given me freedom >> reporter: the vaccine now goes to a much bigger stage 3 clinical trial over the next few years before it could be commercially available. but researchers are hopeful for melanoma and maybe someday other cancers. >> and if we get to the point where you can literally prevent almost everyone from

relapsing, that's a gigantic win >> roxie >> reporter: a win which tonight may be one big step closer. kristen dahlgren, nbc news still ahead on this tenth anniversary, my powerful interview with a boston marathon bombing survivor and the marine who gave him hope

today as thousands of runners took to the streets for the famed boston marathon thoughts of the bombing that killed

three and wounded hundreds at the race ten years ago were not far from mind. for so many that date became a new starting line in their lives. i caught up with some of them. >> what has always struck me is that there was that one moment of evil and then every moment thereafter was humanity at its best >> reporter: an appreciation that for ten years has guided patrick downes and his wife, jessica kensky spectators and newlyweds on that fateful monday >> jess and i both lost our left legs below the knee we were totally helpless we entrusted our lives and our livelihood into the hands of these total strangers. >> reporter: strangers who would truly become shoulders to lean on >> i will never forget that moment. and every time i think about it i get the chills because these five marines walked into my hospital room five days after the bombing. to see these guys, four on prosthetics,

one in a wheelchair, back to life, big smiles on their faces, full of spirit, and it was just the most incredible gift. and then they kept coming back. >> you couldn't get rid of us. >> couldn't get rid of you. >> reporter: retired marine sergeant gabe martinez lost both his legs in an i.e.d. blast in afghanistan in 2010. gabe and other veterans from an organization called semper fi and america's fund immediately set out for boston >> what was the message that you wanted to bring to these folks who were still going through the shock and the trauma of what had just happened? >> the message that i wanted to bring was purely like patrick said, just the hope. >> reporter: just like the hope he had found three years earlier. >> the moment when another amputee, a triple amputee marine walked in my room, it was that same thing. it was like man, look at him like he's what i wanted there's hope >> and you wanted to give that hope to patrick. >> exactly >> we were bonded in a way that i just couldn't have imagined >> reporter: patrick and jessica were

rushed to different hospitals after the blast. and it was weeks before they were reunited together they have overcome dozens of surgeries and rehab. jessica would have her other leg amputated. the bombing didn't define who they were but did define their direction. jessica is a nurse, and patrick a psychologist serving military members, vets and their families >> what i see here is everybody kind of giving forward >> absolutely. i tell people all the time that they might hear about, you know, us marines going out and seeing them. but i tell them, it helped me just as much and probably even more >> you end your broadcasts saying please take care of yourselves and each other. >> i do. >> and not only is that a great call to action, but it's also a really meaningful way to live your lives. and gabe certainly started that chain of reaction that jess and i have really tried to keep going forward >> reporter: a

friendship forged from tragedy. today and every day, boston strong. >> we've been picked up and carried by this unbelievable community. and it's been like the most overwhelming, awe-struck moments of my life. >> and that's "nightly news" for this monday. thank you for watching i'm lester holt. and yes, please take care of yourself and each other good night ♪♪♪ alexex! mateo, hey y how's busisiness? alexex! great. y you know ththat n has s really wororked wonder. thatat's what u.u.s. bank isis. great. y you know ththat n has s really wororked wonder. and d you're grorowing in calififornia? great. y you know ththat n has s really wororked wonder. -yup, , socal, nororcal... -monteterey? -all d day. -a brancnch in ventutura? that's's for sure-e-ah. atms in n fresno? that's's for sure-e-ah. freses-yes. that's's for sure-e-ah. encinitatas? yes, indndeed-us. encinitatas? anaheim? encinitatas? big g time. encinitatas? more guauacamole? encinitatas? i'i'm on a rololl-ay. encinitatas? how about t you? i'm jujust visitining. u.s.s. bank.

ranked #1 1 in customomer satisfafaction h retatail bankingng in calififornia by j j.d. po. i'm raj mathai. right now on nbc bay area news tonight, e-40, the rapper, kicked out of the warriors playoff game over the weekend. today warriors players and his friends coming to his defense. >> i had a lot of empathy for the big fella because i know how he is. >>