year's winner. but posey deserves it. >> three time world series champ. >> two-time all-star. face of the mlb. >> thanks. >> bye. on the broadcast tonight, behind the mask. the brutal isis killer with the knife beheading hostages including three americans. tonight, jihadi john has been identified. what secret intelligence has known about him for years. also, the priceless destruction underway by isis, wiping out some of the most important pieces of histor nbc news exclusive. robin williams' daughter zelda breaking her silence about the sudden loss of her father and the legacy she carries on. and a hollywood whodunit. a shocking heist after the oscars. tonight a big star at the center of a mystery. "nightly news" begins now. from nbc news world headquarters in new york, this is "nbc nightly news."

reporting tonight, lester holt. good evening. the identity of the british-accented executioner, the man who's become the face of isis brutality, has apparently been unmasked. until now he's been known by the nickname jihadi john but a senior u.s. intelligence official confirms to nbc news that a london-raised former university student is a sinister figure whose videotape beheadings of western hostages have horrified people around the world. and tonight with the real name we are beginning to unravel his journey from the neighborhoods of west london to syria to the hierarchy of isis. with more, here's nbc's keir simmons. >> we are an islamic state. >> reporter: his british accent was one of the few clues to his identity. isis prop gand ta videos only his eyes showing from behind a hood. but today he was identified.

he is mohammed emwazi mid-20s, came to the uk in 1994. the son of a well-to-do family that reportedly lives in this middle class london home where police and reporters gathered today far from the syrian desert where emwazi was the isis frontman for a string of murders. american journalist james foley, last august then journalist stephen sotloff, british aid workers, american aid worker peter kassig. and last month japanese hostages haruna ya ka wa and kenji goto. this man hew emwazi in london. does that sound like the man you knew? >> a little bit. i really don't want to be certain, but i can't deny the fact that i do find there were a number of similarities for sure. >> reporter: the reporter who identified emwazi says he wasn't always violent. >> he was a shy person. he was very interested and devoted to religion, devoted to family. >> reporter: he studied computer programming at london's

westminster university leaving in 2009. sources here say emwazi did have connections to extremists in somalia and was known to the british security agencies. but he left britain in 2012 for syria where hee would join isis and become a symbol of their brutality. today the daughter of one slain hostage said identifying emwazi was a good step but she wants more. >> i think all the families will feel closure and relief once there's a bullet between his eyes. >> reporter: and tonight there are questions about how mohammed emwazi was able to leave the uk and join isis despite being on the security agency's radar. and questions about what happened to this british-raised and educated young man that apparently turned him into a world famous and cold-blooded killer. lester. >> keir simmons in london tonight. thank you. the dangerous reach of isis extends all around the world including into this country using the power of social media. the arrest of three men from new

york in what the fbi says was a plot to support isis seems to be the latest example of a rapidly growing trend. and a top fbi official admitted today that we are, quote, losing the battle to stop the spread online. our justice correspondent pete williams is monitoring the latest from our washington newsroom. pete, good evening. >> reporter: lester, good evening. the latest is federal authorities are questioning a man in norfolk, virginia tonight to see if he played a role in raising money for the plan to travel to syria. no charges yet officials say as they continue their investigation. in the brooklyn neighborhood where the men charged with supporting isis lived and worked, a community leader says he'd tried to talk one of them habivoev out of becoming radicalized. >> we had an argument with the gentleman about understanding of the way he understands islam. >> reporter: u.s. officials say the brooklyn men were lured by isis propaganda and that two of them bought plane tickets to get to syria. intelligence agencies say as many as 20,000 people from 90

countries have traveled to syria to fight, many to join isis. they say 180 americans have either gone or tried to. 20 from the u.s. have been stopped in the past year and a half ranging in age from 15 to 63. isis now has social media feeds in 23 languages. and the director of national intelligence said today it's virtually impossible to stop. >> the problem there is their ubiquitous use of the media, and so the challenge is how do you take down the internet? >> reporter: france's interior minister in california last week urged google, facebook and twitter to be more aggressive in weeding out isis propaganda instead of relying on users to flag it, a process youtube says works quickly. some in congress say social media should have zero tolerance for jihadist propaganda. >> we would never allow isis to take out an ad in "the washington post" recruiting folks to go to syria, radicalize and come back and kill us. we wouldn't allow that to occur. >> reporter: in minnesota today

a teenager stopped last may at the airport admitted in court he was trying to get to syria. he pleaded guilty to a terrorism charge and could face up to 15 years in prison, lester. >> all right, pete. isis has demonstrated time and time again its lack of respect for human life. it comes as little surprise that it has no respect for human history either. we're now seeing shocking images of isis members laying waste to priceless artifacts in the very cradle of our civilization. our chief foreign correspondent richard engel has our report. >> reporter: add cultural genocide to isis' growing list of crimes. the group which has killed, terrorized and uprooted hundreds of thousands of people in iraq and syria is now destroying their heritage too. >> translator: we were ordered by our prophet to take down false idols and destroy them says this isis member in a video released by the group, which

includes music and slow-motion sequences. then the men go to work ransacking mosul's renowned museum and a nearby archaeological site, demolishing irreplaceable statues and works of art. some crumble with a mere push. others require more effort. the big ones are defaced with power drills. including this winged bull, a god who protected the asyrian empire 2500 years ago, now powerless against these modern-day vandals. >> to see these pieces being smashed like that is really heartbreaking. >> reporter: archaeologist michael donte has worked in and studied the region for 20 years. >> isis is conducting a war on culture, war on cultural diversity. >> reporter: isis is taking a hammer to history systemically wiping out traces of prehistoric culture in areas under its control. destroying artifacts of civilization itself. richard engel, nbc news, istanbul. back in this country now,

the winter without mercy brought much of the south to a grinding halt over the last 24 hours. paralyzed by yet another storm of snow and ice. while in the midwest and the northeast bitter cold is returning to areas that have already seen records shattered this season. nbc's peter alexander has more on the freeze that feels like it's never going to end. >> reporter: offshore and on ice, dozens of lobster boats frozen in place in maine for weeks now. fishermen unable to do their jobs. in connecticut temperatures diving into the teens, water freezing as it left the hose at this house fire. and in new hampshire a harrowing survival story for dean mullens buried alive for hours after snow slid off his roof right on top of him. >> i had no time to move. it was just moving so quickly. and ended up pinning me on my back. >> reporter: from the midwest to the deep south, punishing cold and snow. >> i'm kind of sick of it, yeah. >> reporter: more than a foot in alabama stranding hundreds of drivers on i-65 overnight. >> take what the road gives you,

you know? and deal with it. and be calm and go slow. and you'll make it through. >> reporter: more than 11 feet in maine, 132.5 inches, tens of thousands still without power in north carolina. and how about that cold? cleveland on pace for its most frigid february on record. both syracuse and bangor en route to their coldest month ever. nonstop. >> nonstop, man. day and night. >> reporter: in virginia we met cornelius williams whose business is showing no signs of cooling off. >> been a nasty winter. >> reporter: still, this winter is producing stunning scenes like nantucket's nearly frozen waves. this wald eagle keeping her little once warm. and along lake superior so cold it's now safe for wisconsin's famed ice caves to welcome guests again. spring barely three weeks away. peter alexander, nbc news, arlington, virginia. >> and don't look now, just about three weeks to spring and there is another big snowmaker on the way for much of the country.

janice huff is in the weather center. janice, notice i no longer ask you if there's relief in sight. i know the answer. >> you know what, lester, some parts of the northeast that have been dealing with this brutal cold for so long will get a bit of reprieve next week for a brief time but overall we're still stuck in the pattern. yes, now, a snowstorm that will be dropping over the southern rockies is going to move out into the plains over the next couple of days. so for tonight around denver south towards albuquerque in the higher elevations up to a foot of snow expected. that spreads towards dallas on friday afternoon with some light snow, looking like maybe one to three inches there up towards oklahoma city. and then another snowstorm, another piece of energy forms another snow area on saturday afternoon. that's wichita, oklahoma city, that spreads towards st. louis by sunday morning and then towards chicago later in the day on sunday and the afternoon. south of that towards cincinnati a mix of rain, maybe some sleet in the warmer air. temperatures across much of the northern tier are still in the single digits. windchills are still below zero

in many spots. and we're still going to see waves of that cold coming through over the next several days, lester. >> janice huff, thanks very much. now you've heard all this talk about the future of the internet. it may have just been decided in a landmark vote today by the fcc. it concerns net neutrality, which supporters say will ensure open access to the web for everyone. opponent, however, say it amounts to government control over the internet. nbc's tom costello explains what it all means for you. >> reporter: to understand what net neutrality means, think of the internet as a sort of supercongested highway with most of the wider lanes being taken up by big fat trucks carrying content like amazon netflix and hulu. the fcc's new rule means those big companies would not be able to pay to dominate the fast lanes. all of us from students studying at home to mom and pop businesses to the amazons of the world will be guaranteed equal access to the fastest services.

>> the internet is simply too important to allow broadband providers to be the ones making the rules. >> reporter: the new fcc rules will also prohibit internet service providers like verizon, at&t and comcast, nbc's parent company, from slowing down internet traffic and blocking access to competitors. that means a vast majority of us will see no change to our internet service and internet providers will not be able to limit what we see at home or on our smartphone. >> this is about preventing a future where some websites would have gotten preferential treatment over other websites. >> reporter: critics say the new rules amount to government overreach. >> this is not what the internet needs, and it's not what the american people want. >> reporter: expected now, a vigorous legal challenge to this new law of the web. tom costello, nbc news, washington. we turn now to a hollywood mystery after the oscars, a heist involving one of the biggest stars on the red carpet. academy award winner lupita nyong'o, she's missing something that's very expensive that tens of millions of people just saw

days ago stolen right out from under her nose. nbc's hallie jackson reports on the race to find it. >> reporter: it's a hollywood whodunit. a jaw-dropping dress that dropped off the radar. >> the exquisite lupita nyong'o. >> reporter: just three days after actress lupita nyong'o wowed at the oscars winning raves on the red carpet. nyong'o says it took a village to get her into the gown, weeks to create it, but it disappeared in a matter of minutes from a high-end hotel in west hollywood where the actress had been staying. the custom calvin klein created from 6,000 rare pearls worth an estimated $150,000. >> i have never, ever heard of an oscar gown being stolen. >> reporter: this dress has become so famous. what can you possibly do with it once it's been stolen? >> it's true. they can dismantle the dress, restring the pearls and nobody would know those pearls came from that dress. >> reporter: l.a. detectives hope surveillance video from the

hotel, which says it's working with police, tips them off to whoever took the dress. nyong'o's not commenting and neither is francisco costa, one of the designer who helped elevate the actress' award season looks. for a fashion icon it's now a stunning wardrobe malfunction no one saw coming. hallie jackson, nbc news, los angeles. a lot more news ahead tonight including our nbc news exclusive. breaking her silence about the tragic loss of her father. robin williams' daughter speaks for the first time about the questions surrounding his death. also, the slow-speed chase in the wild west that captivated folks all across the country today. the ending, you just got to see for yourself.

in the six months since his death, robin williams' family hasn't said much publicly, preferring to mourn in private. but now his 25-year-old daughter zelda is breaking her silence in an exclusive interview with our national correspondent kate snow about her father's legacy and how she copes with questions surrounding her sudden loss. >> it gets a lot of attention. >> reporter: after her father's death zelda williams tattooed a hummingbird on her right hand because she wanted to see it every day. >> i like hummingbirds. hummingbirds are fun and flighty and strange. it's hard to keep them in one place. and dad was a bit like that. keeping a conversation in one moment was impossible with him. >> look at the car! look at the car! look at the car! >> for me it was a reminder i wanted. >> reporter: i lost somebody to

suicide, too, so i know that there's often that sort of, why did this happen question. >> i don't think there's a point. >> reporter: you'll never know. >> no and it's not -- it's not important to ask because it's -- >> reporter: done. >> yeah. >> reporter: that seems to me what all the people who knew your dad as a fan, all the people that loved him and his work, when it happened everybody wanted to know why, how could this happen. >> diseases are, until we find out exactly how they work, we don't have an explanation. a lot of people who have been through it and lost someone in any way, the ones that i found that have gone on to lead very full lives found that they just had to know that there's no point questioning it and there's no point blaming anyone else for it. there's no point blaming

yourself or the world or whatever the case may be because it happened, so you have to continue to move. and you have to continue to live and manage. >> reporter: on friday in los angeles zelda williams will present a noble award to a group robin williams worked with for years that provides prosthetics to athletes with disabilities. >> he's done charity as long as he had the wherewithal and the ability to do it. that was what his favorite thing other than comedy really was. >> reporter: zelda wants to carry on her father's charitable work because it was so important to him. >> hello! >> reporter: she knows she's not the only one who misses her father and everyone has a favorite memory. >> nanu-nanu. >> the world, as i said, keeps spinning. doesn't mean he was never on it. >> reporter: kate snow, nbc news, los angeles. and we've got more to tell you about as we continue tonight. we'll be back with a story that got a lot of our viewers talking. also, excitement building tonight after a mysterious announcement by apple.

a mysterious announcement today from apple revealing it will hold an event on march 9th with a message that reads simply "spring forward." it comes amid speculation that the launch of a highly anticipated apple watch is near. the company has previously said the watch would ship in april. a major moment for gabrielle giffords, the former arizona congresswoman who survived a shooting attempt on her life. a navy combat ship named in her honor hit the water for the very first time this week in alabama. it won't officially launch until later this year. in the meantime the "uss gabrielle giffords" will get some finishing touches. and about last night, we had an overwhelming response to our "making a difference" story. we brought you about the prospector movie theater in ridgefield, connecticut, and its mission to give people with disabilities what they say they want most, jobs and meaningful employment. the staff watched from the theater and sent us this photo. they've heard from people across the country, some who want to bring the idea to their own communities.

if you missed the report, it's on our facebook page at nbcnews.com. i hope you'll take a look. we'll continue to follow their story. when we come back here tonight, the chase that made people across the country drop everything to watch. "nbc nightly news" is brought to you by pacific life. for insurance, annuities and investments, choose pacific life. the power to help you succeed.

it was a desperate chase today for two fugitives and it gripped the nation as it played out live on the tv. in the spirit of butch and sundance, or maybe thelma and louise, they made a break for it together in the phoenix suburbs. but these were no ordinary outlaws and reining them in was no easy task. nbc's miguel almaguer has the wild tale. >> reporter: in sun city today this may have been the very definition of the wild west, a slow sometimes high-speed pursuit of two llamas on the loose breaking away from their owners, at times from each other, seizing their moment and their shot at freedom. >> something you don't see every day. >> we'll keep an eye on this, folks. >> reporter: the two-hour chase carried live on local, even cable news. this wild tale dubbed llamas on

the lam. the llama drama trending on twitter. the arizona cardinals agreed to one-year deals with llamas on the loose. the llama chase, the biggest since o.j. it's gotten wild out west before. we've seen bears in backyards running from the law. >> there goes mama climbing up to get her baby. look at that. >> reporter: ducks have made a dash, or at least a slow waddle along the freeway. and a moose on the loose brought traffic to a standstill. but this was llamas. llamas! >> at one point one of the deputies was trying to capture a llama with crime scene tape. you know what he had at his disposal. that obviously didn't work. >> reporter: like most getaways it didn't end well for the suspects. running out of breath and time can they were lassoed by modern-day cowboys. a good run while it lasted. miguel almaguer, nbc news, los angeles. that will do it for us on this thursday night. i'm lester holt. for all of us at nbc news, thank you for watching and good night.

i pray for intervention but we ultimately fear the absolute worst. >> right now at 6:00 the terror in the middle east is hitting close to home. good evening. thanks for being with us. i'm raj mathai. >> >> tonight a northern california couple is fearing the worse, but they are praying for mercy. their prayers for family members in syria kidnapped by isis militants. those militants stormed the village where the family lived and took hostages with them.

mark mathews met with them today in modesto. it must seem unreal to them. we are outside the church with they attend and neighbors were planning a candle light vigil tomorrow. they have been in touch with family members. they are trying to bring attention to the plight of their family members in syria in hopes of bringing some help. ramel and charlotte david tell me the call came sunday afternoon from a nephew in syria. >> that happened in monday morning. at 4:00 in the morning. all of them wearing black uniforms. >> and they took everybody. and we don't know what they add to it.