out. >> taking us back to our high school reading days. >> thanks for joining us at 5:00. brian williams is next with "nightly news." >> have a good night, folks. on our broadcast tonight, is it a turning point? as isis finds a new way to shock the world with the execution of a jordanian air force pilot. jordan vows revenge for the death of a fellow muslim, and tonight what we're learning about the american woman being held. the vaccine debate. despite a mountain of evidence that they're safe and save millions of lives, the reason so many parents are choosing not to vaccinate their children. three-parent babies. the world watches a pivotal decision of the in vitro fertilization. some fear a world of designer babies. the surprise sequel to the american classic "to kill a mocking bird." turns out the reclusive harper lee wrote another novel, and much to the excitement of readers everywhere. "nightly news" begins now.

>> announcer: from nbc news world headquarters in new york, this is "nbc nightly news" with brian williams. good evening. the terrorist group isis so determined to shock civilized people everywhere has now resorted to a new method of murder. they have executed a jordanian air force pilot by burning him alive, and we'll point out just as quickly here we're not going to air a bit of that here tonight. this execution, while no more vile than any of the others may be different in terms of how jordan now reacts to the murder of a pilot and a muslim and in the background here is the knowledge that an american woman is also being held by the same group. we have it covered tonight beginning with our chief foreign correspondent richard engel. richard, good evening. >> reporter: good evening, brian. there is absolute outrage in jordan. people are furious. they are shocked. there are calls for military action. and there's been a strong show

of support for the monarchy. locked in a metal cage, doused in fuel, the young jordanian pilot moments before being burned alive. the most savage act yet from a group known for its shocking brutality. in jordan, relatives could not contain their disgust and grief and fury. the pilot was first lieutenant muath kasasbeh 26, just married in july an elite member of jordanian society. he was captured a day before christmas after ejecting from his f-16 on a mission to attack isis in syria, part of the u.s.-led coalition. jordan's king abdullah, a close u.s. ally at the white house today before cutting short his washington visit. earlier on jordanian television, he called the murder cowardly terror by a group with no relation to islam. president obama said the killing

intensifies his determination to fight isis. >> should this in fact be revealed to be authentic, it's just one more indication of the viciousness and barbarity of this organization. >> reporter: jordan had been considering a prisoner swap for the pilot, exchanging him for three militants on death row including this woman, captured after her suicide vest failed to go off during a 2005 attack on three hotels in amman. 60 people were killed. jordan said last week it would free her but first wanted proof that its pilot was still alive. in fact, jordan believes he may have already been dead, burned alive just days after his capture. and that woman on death row, jordan said it will execute her and five other militants as early as tomorrow, brian. >> richard engel, starting us off tonight. richard, thanks. again, about this other hostage

being held by isis. another american, a 26-year-old woman. we haven't heard much about her case publicly until now. as the president has spoken about the situation for the first time. andrea mitchell at the state department in washington for us tonight. andrea, good evening. >> reporter: good evening, brian. the horrific murder of the jordanian pilot has only intensified efforts to find that last known american being held hostage by isis, the woman. into the chaos of syria's civil war, amidst militias and terrorists, she went unarmed. hundreds of thousands already dead, millions more wounded or displaced. a 26-year-old american woman working for aid organizations, trying to help the war's millions of refugees. taken hostage a year ago august. her name, hometown and organization all withheld at her parents' request. but always top of minds at the white house, as the president told savannah guthrie this week. >> what's being done to help her?

>> we're in very close contact with the family trying to keep them updated. obviously, this is something that is heartbreaking for families. and our obligation is to make sure we can do anything we can to try to make sure that any american citizen is rescued from this situation. >> reporter: but isis has wiped out borders, forcing the u.s. to rely on murky contacts and often unreliable foreign intelligence services. the only positive sign, isis has never acknowledged capturing the aid worker, and executing a woman on camera might be deeply offensive to isis followers. >> as brutal and unpredictable as isis is there's also reason to believe that they're not intent on killing female hostages. >> reporter: in fact isis has never paraded the american woman among the other hostages. leading some to hope, her family to pray, that she may still be alive. brian? >> andrea mitchell at the state department for us tonight. andrea, thanks. today republican senator rand paul of kentucky went to the physician's office in the u.s. capitol, took off his dress shirt and got a booster

vaccination for hepatitis a, and he made sure a camera was there because he has spent the last news cycle tangled up in the debate over vaccines. yesterday on cnbc, he said in part, he was aware of many tragic cases of walking, talking, normal children who wound up with profound mental disorders after vaccines. well, today the senator, who is an eye doctor said he was annoyed that he's being characterized as somehow anti-vaccine. he said the science is clear and vaccines are safe. this debate has blown up after the measles outbreak in california, which has now spread to 14 states. our update tonight from nbc's hallie jackson. >> reporter: today employees washed toys outside the california day care where an infant infected with the measles may have exposed 14 other babies. part of an outbreak that began at disneyland. that company's ceo now says there's been no impact on park attendance.

>> this is a time for parents with kids under vaccination or inoculation age to be cautious about taking their kids to public places, not just theme parks. >> reporter: the growing outbreak seems startling for those who remember what it was like before scientists developed a safe vaccine in the early '60s when the virus hospitalized 48,000 people each year and killed 400 to 500. one victim, the daughter of beloved children's author roald dahl. decades after he begged parents to vaccinate, writing of his 8-year-old i feel all sleepy she said. then within 12 hours she was dead. most younger people nowadays never lived through measles. which may be why a recent poll finds americans under 30 are less likely to support mandatory childhood vaccinations. patty bailey wants them. her child reed has cystic fibrosis and can't get the measles shot. >> i think it's about time someone stood up and had a good example of a child that can't

receive a vaccine but that needs the community around him to support him. >> reporter: the cdc recommends immunization, but it's up to states to create the laws. mississippi, which has the nation's highest vaccination rate, almost 100%, only lets parents opt out of measles shots for medical reasons, not personal or religious ones. in colorado, where the law is much less strict, only 81% of people have been immunized, the lowest in the country. globally about 110 other nations have better vaccination rates than the u.s. including china, russia and iran. on capitol hill, meanwhile, a rare show of consensus. >> it's really a slam dunk what the decision should be. >> reporter: for lawmakers and doctors, get the shot to stop the spread. hallie jackson, nbc news, los angeles. one more note on this tonight, we're joined by dr. nancy snyderman. and nancy, i know your view is, forget measles. the comebacks could not perhaps stop at measles. >> you and i have sat here for the last few months talking

about whooping cough, mumps and now measles. these outbreaks aren't an accident. they're happening because we've become rather lax. we forget what these diseases look like they forget that they kill we forget that a simple vaccine can prevent these illnesses. it's inherently important that those of us who are healthy vaccinate ourselves to protect those who are less vulnerable in society. that's why it's called public health. what concern meese is this may be the canary in the coal mine. we see a break in public health in this country. there's no debate. vaccines save lives. what if a year two years from now, you and i are sitting here talking about the first case of polio in this country? i don't think we can be so cocky as to say that can't happen. so this should be the call to arms. >> dr. nancy snyderman with a cautionary note here. after our coverage, thank you, nancy, as always. our weather continues to make news as millions are in the grip of a cruel kind of cold, clear to the eastern seaboard. many communities saw yesterday's

highs cut in half still. parts of the northeast which saw a record number of snowfall over the last week have flash frozen, leaving the roads an icy treacherous obstacle course. nbc's miguel almaguer is in boston for us again tonight. miguel, good evening. >> reporter: brian, good evening. this is one of three snow farms in city of boston. it's where they bring all the powder to thaw. our camera is 40 feet up on a snow pile that is four stories deep. i want to give you even more perspective. this snow farm runs the length of a football field. there are mounds of snow on both sides of this access road. tonight the city says there's no more room here, but another storm is on the way come thursday. today the desperate break from falling snow but no relief from bone-chilling cold. the arctic blast dropped the windchill to negative 13 degrees in boston. >> hypothermia can turn serious very quickly. >> yes, it can. >> reporter: at mass general they fired up the hypothermia

cocoon, a bubble to bring the freezing back from the brink. >> patients that have burn injury greater than 20% of their total body surface area will come in here because it provides a lot of heat and it also provides moisture. >> reporter: the deep dive in temperatures felt across the nation. in denver, cheyenne, kansas city and rapid city today's highs will plummet in half by tomorrow. across the region, a flash freeze. whiteout conditions in southern minnesota triggered back-to-back multi-vehicle pile-ups. black ice can be deadly. >> look down the road as far as you can. >> reporter: we were shown firsthand how treacherous slick roads can be. when you're not familiar driving on snow and ice, even simple maneuvers can become more dangerous, even on a closed course like this one, experts say braking can take 10 to 15 times longer. speed wasn't a factor in boston. record snowfall this week turned today's commute to a crawl.

>> received over 40.1 inches of snow. we're looking at possibly another six inches of snow on thursday. >> reporter: with snow farms at capacity, massive melters like this one are being trucked into the city but tonight back roads are still a mess. on-demand plowing is now an app. >> they just go click on the app, request a service, and look out their window and watch us take care of their work for them. >> reporter: brian, this is one of three snow farms in the city of boston. it's completely packed. the city said they can't bring any more snow here. but as we mentioned, they'll get another few inches here on thursday. brian? >> miguel almaguer on the road in boston tonight. miguel, thanks. and then there's the west coast. they're about to get a deluge of heavy rain beginning tomorrow. the so-called pineapple express, that flow of atmospheric moisture that stretches out clear from hawaii, is expected to deliver an enormous amount of precipitation. california, oregon, washington, part of idaho, montana, could all see several inches of rain from this.

with flooding and landslides a possibility. possible proof of life tonight from cuba. after months outside of the public eye, fidel castro wants the world to know, despite endless rumors to the contrary, he is very much alive. new photography emerged today showing the 88-year-old former cuban leader, the first time we've seen anything of him since august of last year. still ahead for us this evening, so-called three-parent babies. a closely watched decision today. what was once the stuff of science fiction, now very much a reality. and not everyone welcomes it. also, in a day and age where it's really tough to shock people anymore, the huge surprise today that no one saw coming.

it's an idea that bends the mind as well as the established laws of nature. one baby with three genetic parents. and while some call it playing god, those who support this in vitro technique say it can greatly increase the chance of having a healthy baby. it is not legal yet in any country, but it may come to the uk first. nbc's katy tur reports from london tonight on how it works and why parents might want it. >> reporter: at first glance little jessica holliday looks like any happy, healthy baby. but look closer, and you'll find the 13-month-old struggles to swallow and hold her head up. jessica has a genetic disease that will prevent her from every

walking or talking. and there is no cure. >> when you're told that your daughter's going to die, it's really, really hard to take. and then for them to say, oh, by the way, any more children that you have would also have the disease. it leaves you with no hope for the future. >> reporter: but today uk lawmakers took the first step to give parents like the hollidays back that hope while entering a brave new world of genetic science. >> so the ayes have it. >> reporter: moving to allow so-called three-parent babies to eliminate certain genetic mitochondrial diseases. mitochondria are the power source. when they're defective they don't fuel healthy development. this new treatment solves the problem by taking the parents' dna and combining it with a healthy mitochondria of a third party, a donor woman. so the third parent involved is only giving their healthy might o kond

-- mitochondria which has no identifying characteristics? >> that would be correct. >> reporter: it may seem like a small step beyond in vitro fertilization, but experts say it is a big step in our ability to manipulate life. >> today's step means we can take diseases 100% lethal and alter the course so that a husband and wife can have a healthy baby. >> reporter: detractors say this new step is a slippery slope that could lead to genetically customized designer babies. but for parents like vicky holliday -- >> there's no words. it's absolutely incredible. >> reporter: -- it's a new chance for a healthy child. katy tur, nbc news, london. we're back in a moment with news for anyone who works out. when it comes to one particular form of exercise, it turns out, less is more.

veronica and i are trying a new fad called jogging. i believe it's jogging or

yogging, it might be a soft j. but apparently you just run. >> it was indeed once rare to know a jogger, but then it became widespread exercise. now the "journal of the american college of cardiology" says too much jogging could be as bad for you as not jogging at all. they found moderate jogging in terms of distance and speed and time was good for the heart, but out of a thousand joggers studied, those who ran over four hours a week had the same death rate in the end as those who got no exercise. there's only so many office products, yet there are so many places to buy them, so the two biggest names are talking about joining forces apparently. there are numerous reports that staples and office depot are in advanced merger talks. the fed stopped a similar effort almost 20 years ago out of antitrust concerns but that was before both chains faced competition from the web and big box retail stores. william holden and cliff robertson brought them to the big screen, but in real life in world war ii, the devil's

brigade was a first-rate american/canadian joint special forces commando unit. today the surviving members who are able received the congressional gold medal many years delayed. they once numbered 1,800 young men back in 1942. when we come back, for decades we thought the story was over, but an american classic is now getting a sequel after all. nbc "nightly news" is brought to you by pacific life. choose pacific life. the power to help you succeed.

the great american novelist harper lee gave us a great american book, "to kill a mockingbird," and then she disappeared. she gave her last wide-ranging interview when jfk was president. she lived in relative seclusion ever since. reportedly now in fragile health at the age of 88. all the while and for all these years, book lovers and publishers alike wanted more. maybe just one more book, and soon we're going to get it. because it turns out harper lee wrote another novel. a manuscript that everyone thought was lost, including the

author herself. we get the story tonight from our national correspondent, kate snow. >> one book, the last few years, has been so warmly embraced. >> reporter: for decades, a must-read, immortalized in the oscar-winning film. >> you never really understand a person until you consider things from his point of view. >> reporter: "to kill a mockingbird" was harper lee's only book. now her publisher said they recently discovered another work. >> we devoured it. >> reporter: it's not a new book, but essentially a first draft written in the 1950s of what would become "to kill a mockingbird." >> it was submitted to her publisher in 1957, and she was then told to rewrite the book from the point of view of the young scout. >> reporter: scout is a grown woman, back from new york to visit her aging father in alabama. author and filmmaker mary mcdonough murphy said the 304-page manuscript was discovered in a bank safe deposit box.

>> harper lee's sister died and in the course of cleaning out this deposit box, lo and behold here is this manuscript attached to the original manuscript of "to kill a mockingbird." >> how do we know this is real? >> you can see it's written on a manual typewriter from the period. it has on the front of it the address where harper lee was living at the time in new york. but if you read the book more importantly, only harper lee could have written this novel. >> reporter: in a statement, lee said she passed the manuscript around to trusted friends to make sure it was worthy of publishing. writing, i am humbled and amazed that this will now be published after all these years. >> her first novel came out of the blue a bolt out of the blue and then we never heard from her again. so the fact that we get to hear from her now is really exciting. >> reporter: for a new generation of readers, a new ending to an iconic american story. kate snow, nbc news, new york. that is our broadcast on this tuesday night. thank you for being here with us. i'm brian williams.

we, of course, hope to see you right back here tomorrow evening. good night. . nbc bay area news starts now. right now at 6:00 no charges. why investigators decided to let the man under the sheet go. he was the prime suspect, though, in san francisco's body parts case. good evening everyone. thanks for joining us. i'm jessica aguirre. i'm raj mathai. new twists to this gruesome case. in the past few minutes shall the public defender tells us the prime suspect in the body parts case is relieved. this after the district attorney tells us he does not have enough

evidence to charge him. this stems from the body parts found in a suitcase. nbc bay area mark mathis joins us where that man could walk free any moment. mark? >> true mark an dras could walk out any time this evening. we expect that he will. the district attorney is not going to charge him because, as the d.a. said there's not enough evidence at this point. they're waiting on the medical examiner to determine the identity of the body in the suitcase and the cause of death and just minutes ago, as you say, public defender jeff adachi broke the news to mark andres here at the jail. >> mr. andres was extremely relieved and i understand that he's going to be released today in a few hours. >> the district attorney issued a statement saying that he had reviewed the evidence and has decided not to file charges against mr. andres at this time. >> 59-year-old mark jeffrey andres was arrested on saturday at this public housing project on turk street. police walked him out covered in a