brian williams. see you back here at 6:00. on our broadcast tonight, the tragedy at fort hood. the suspect who opened fire. were there warning signs? tonight, the investigation, what witnesses saw, what we've learned about the victims, all members of the military. outbreak. the first major tornado threat of the new season. a huge system on the move tonight. miracle drug. that's what they're calling the treatment that's bringing overdose victims back to life, just approved for many desperate families to use in case of an emergency. and family portrait. jenna bush hager with her father, the former president, on his paintings and his life these days. also tonight, the surprise announcement from a television legend. "nightly news" begins now.

good evening. fort hood in texas is once again in mourning. once again, one of their own has opened fire on fellow military. three are dead, 16 wounded. all of them members of the military. the suspected gunman here was 34, a veteran himself. while there's still no known motive, we're learning more about his mental health history. this is, of course, the second tragedy, the second mass shooting in five years at fort hood. ironically, its longtime nickname is "the great place." fort hood is one of the engines that makes the u.s. army go. so many of our recent vets have cycled through there. the base is loaded with combat veterans from iraq and afghanistan. from the three-star commanding general on down and now this. and there are so many questions remaining tonight. we want to begin our coverage with nbc's mark potter at the main gate. mark, good evening. >> reporter: good evening, brian. fort hood is once again reeling from its second shooting rampage

in five years, as you said, and there are many questions about why this happened and could it have been prevented. a woman who acknowledged she is the wife of the alleged fort hood gunman seen today leaving her killeen, texas, apartment. >> we have an active shooter currently on fort hood. >> reporter: the alleged shooter, 34-year-old u.s. army specialist ivan lopez, believed to have brought his own gun onto the base. >> it's going to be the 33000 block of 72nd street. we have multiple gunshot victims. >> reporter: military officials say lopez entered a building in the first medical brigade and opened fire with a .45-caliber handgun. he then got into a vehicle and continued to shoot. >> just with advised, they're saying that the vehicle was a dark toyota camry. and it was a unit, a specialist that's actually active shooting. >> reporter: next lopez walked into another building and opened fire. at the transportation brigade's administration building, he was confronted by a military policewoman, and he died of a

self-inflicted gunshot wound in the parking lot. it was right here on the steps below their apartment that lopez's wife first heard her husband had been identified as the shooter and had killed himself. a neighbor had left her door open with the tv on, and that's how she got the news. >> she broke down. she said, oh, my god, it's him. she broke down. >> reporter: among those killed, 37-year-old sergeant timothy owens. a counselor and ten-year army veteran. he just remarried last august. >> very proud of him because he was fighting for our country. >> owens had two teenaged children. his daughter posted on facebook, i hate that you were taken away from me. i love you, daddy. injured yesterday, 32-year-old major patrick miller. >> when i called his phone, a lady answered. i said, who is this? she told me what was going on. >> reporter: also injured in the shooting is keshia fountain. >> right now, i feel pretty good for our patients. but we still have some time to go before i'm going to completely declare them out of

the woods. >> reporter: in the 2009 fort hood massacre, u.s. army major nidal hasan shot and killed 13 and wounded more than 30. he was convicted and sentenced to death. authorities confirm hasan and the latest suspect, ivan lopez, both bought their weapons legally at guns galore in killeen. today, flags are flying at half staff throughout killeen in honor of the fort hood victims. tonight, the military said there were several acts of heroism during the shootout as victims' families are left to make sense of another senseless tragedy. brian? >> mark potter at the main gate of the place they call the great place of fort hood, texas. mark, thanks. when these kinds of things happen, people's thoughts turn automatically to the possibility of combat stress. and today we learn more about this gunman's medical record and his military record. our pentagon correspondent, jim miklaszewski, picks up that end of the story. jim, good evening. >> reporter: brian, defense officials tonight describe 34-year-old specialist ivan

lopez as an underachiever who in 15 years of military service went largely unnoticed until now. as a 19-year-old, lopez joined the army national guard in puerto rico. in his hometown guayanilla today, family friends were shocked by the news. >> translator: he was a normal kid, always obedient. >> reporter: in 2008, he signed up for the army infantry at ft. bliss, texas. on capitol hill today, army chief of staff ray odierno called lopez an experienced soldier. >> had a one-year deployment to the sinai with the national guard and then had a four-month deployment in iraq. >> reporter: by then, lopez was a truck driver at the end of 2011. but records show he never saw any action. military officials say, however, that lopez did suffer depression, anxiety and sleep deprivation. but a psychiatric exam at fort hood last month raised no red flags. >> we have very strong evidence

that he had a medical history that indicates unstable psychiatric or psychological condition. >> reporter: the army was in the process of determining whether lopez suffered posttraumatic stress. up to 20%, one in five veterans of the wars in iraq and afghanistan have been diagnosed with ptsd. approximately 300,000 soldiers and marines. but veterans advocates warn, ptsd can be impossible to diagnose. >> there's not a single thing that we can look for. there's not a single sign that we can examine. it hits different people in different ways. >> reporter: last week, the iraq and afghanistan veterans of america planted nearly 1,900 flags in the mall in washington. one for every veteran who has committed suicide so far this year. but the group's founder, veteran paul rieckhoff, insists their suffering and sacrifice is in no way connected to the events at fort hood. >> it's very important that we

don't define 2.6 million veterans of iraq and afghanistan by the tragic events of one gunman on a terrible day. >> reporter: the investigation into what may have driven lopez into this shooting spree has just begun. but military officials already acknowledge they may never find the answer, brian. >> jim miklaszewski at the pentagon tonight, rounding out our coverage of this latest tragedy at fort hood. the weather is making news in this country tonight. from texas on up into the midwest, millions are facing the threat of more severe weather, including the first real threat of this season from tornadoes. that's on top of damaging storms just last night and earlier today. weather channel meteorologist mike seidel following it all from north little rock, arkansas, where they're under a tornado watch presently. mike, good evening. >> yes, brian, good evening. that watch is until midnight tonight. it was a long, cold, snowy winter here in the midwest. that put the cap on the tornado tally for march at only 21. only 20% of average. but that threat for twisters is

back tonight and friday. hail the size of golf balls thunder down from missouri to kansas, damaging homes and cars, triggering a threat of severe storms and tornadoes from texas into the midwest. an ef1 tornado tore through university city, missouri, this morning. >> early this morning, it was the sound of this storm that woke everybody up. >> reporter: 100 homes damaged, trees down and nearly 7,000 people left without power. in st. louis, the rain came fast and was heavy, flooding streets and stranding cars. >> it's more than what the drainage system can handle at one time. you have the flash flooding and before you know it, you're in it. >> reporter: at least seven states and more than 50 million people are at risk for either tornadoes or wind damage. central indiana saw 2 to 3 inches of rain, forcing roads to be closed. in southern minnesota, a bizarre weather combination. >> we're in a blizzard warning. then you get a tornado. just weird.

>> reporter: this family's shed was sliced in half. the tornado scattered debris throughout their yard and nailed a piece of wood directly to the side of a building. several states will remain under a tornado watch through most of the night. >> a lot of places could get damaging winds maybe gusting over 70 miles per hour. a very dangerous situation in the overnight hours when you can't see the tornadoes coming. >> reporter: and here's where you need to be vigilant tonight. check out the orange zone in the midwest. tornado watches from here to st. lois until midnight. they'll be shifting east overnight. in the upper midwest, yet another winter storm here in early april. we have winter storm warnings, minneapolis to marquette where they could see over a foot of snow tonight. and, brian, the storms here will move east tomorrow towards atlanta and the appalachians. but the good news tomorrow is, more of a straight-line wind damage threat. the tornado threat will lessen tomorrow as you head east. brian? >> mike seidel going into what could be a sporty night in little rock and the surrounding area. mike, thanks. the obama administration scrambling tonight to explain a

secret u.s. government program aimed at bringing regime change to cuba. while that concept may not be anything new, the weapon is. it's a social media campaign modeled after twitter, aimed at young people, run by the u.s. government's leading agency for humanitarian relief. we get more on all of it tonight from our chief foreign affairs correspondent andrea mitchell. >> reporter: the u.s. has been trying to get rid of the castro regime for decades. 50 years ago, the cia even plotted to kill fidel castro with an exploding cigar. nowadays, the u.s. tries to sow dissent through social media, enticing cubans to join a free network similar to twitter, in a country where internet access is severely limited and tightly controlled. it was called zunzuneo, cuban slang for "hummingbird." run by sham foreign countries and financed through cayman bank accounts. users never knew it was created by the u.s. government's global relief agency, usaid.

better known for helping after disasters like the haiti earthquake and pakistan floods. according to documents obtained by the "associated press" and shared with nbc news, the program created when hillary clinton was secretary of state was to operate below the radar. the contractor warned, there will be absolutely no mention of united states government involvement. >> we were told we couldn't even be told in broad terms what was happening because, quote, people will die. >> reporter: why the secrecy? >> sometimes the work we carry out is carried out discreetly in the context of keeping people who are doing this work safe. >> reporter: but critics say the program risks the safety of young cuban users who also didn't know the u.s. was capturing their personal data. the senator in charge of the agency's budget said he didn't know about it. >> i think most people will tell you are you out of your mind. this is not a program usaid should be involved with. >> reporter: in havana, claudia garcia said, they've always been trying to harm our country and government. but ms. hernandez says it's a good thing so people realize

what's going on in the outside world and things change in cuba. the program has been disbanded but now congress is asking questions, especially because this controversy could affect the future of a usaid contractor, alan gross, jailed in cuba even before this program was launched for having communications gear. now in failing health, desperate to be released. brian? >> andrea mitchell tonight on capitol hill for us. this week of sad mourning continued today in boston where thousands turned out from across the country to honor one of their own. michael kennedy, the second of two boston firefighters, laid to rest after that awful brownstone fire fought in 50-mile-an-hour winds last week. kennedy was just 33. he was remembered for his heroism, his selflessness, his volunteer work with burn victims and big brothers and big sisters in boston. and as a final salute to this fallen marine veteran of the iraq war, bagpipers played the marine corps hymn. still ahead for us tonight, a major move to combat the epidemic of overdoses in america. the drug just approved for

use in an emergency brings people back to life. and later, the announcement from the reigning dean of late night that shocked his studio audience and will his millions of fans.

a shocking number out today from the government. a person dies in this country every 36 minutes from an opioid drug overdose, either prescription painkillers or heroin. and the fda says accidental drug poisoning has now surpassed car accidents as the leading cause of accidental death in this country. there is a drug that can reverse an overdose and stopeople from dying. some emergency responders have been using it. today the feds took a major step in making sure that drug is even more widely available. we get our report tonight from our national correspondent, kate snow. >> reporter: in portland, maine, we rode along with paramedics who routinely use a drug called naloxone to bring someone back from an overdose. >> it's an amazing medication.

they can be unconscious, not breathing and they wake right up. >> reporter: nationwide, the drug has saved more than 10,000 people. and today, the fda approved a new version that can be prescribed to families and friends of someone who might overdose on heroin or opioid painkillers. >> this approval today will enable care -- emergency care, life-saving care to be given on the spot when it's needed, whether you're in a clinic or a hospital or on the street. >> reporter: the new device called evzio, which will be available this summer, talks you through a quick injection through clothing. >> injection complete. seek emergency medical attention. >> reporter: the fda compared it to having a defibrillator around in case someone has a heart attack or an epipen for allergic reactions. until now, access to naloxone has depended on where you live. outside boston, they train dozens of parents each week to news a nasal spray version of the drug -- parents like jack

riley. >> why would you not provide a resource that could allow a parent or loved one to save the person? >> reporter: but in other places, it's illegal for parents to have. maine's governor paul lepage has opposed legislation to widen distribution in his state. do you believe it should be distributed to parents -- >> no. >> reporter: why not? >> because it's an escape. it's an excuse to stay addicted. i think we need to treat -- let's deal with the treatment, the proper treatment and not say, go overdose and, oh, by the way, if you do, i'll be there to save you. >> reporter: but with all due respect, governor, if it can save one life, why would you not support that? >> i've said my peace on it. >> reporter: the fda commissioner says there's no scientific evidence to show that people abuse heroin or painkillers more when they know that there's naloxone around. there are so many families so desperate for this drug, they're getting it from the underground right now. we'll meet some of them next week in a special series across all of nbc news, brian, about the heroin epidemic here in america.

>> we'll look forward to that. an important topic. kate snow, thank you very much, as always. we're back in a moment with a big change coming in the media business.

late this afternoon in the ed sullivan theater here in new york, david letterman stunned his studio audience during the taping of tonight's show by announcing that he plans to retire in 2015. dave is now the dean of late night, up against jimmy kimmel on abc and jimmy fallon here on nbc, who's built upon jay leno's lead and increased his lead over dave letterman in the ratings. just last night, letterman with help from bill murray moved his entire studio audience across 53rd street for a lady gaga concert next door in the roseland ballroom, which is shutting down. it was reminiscent of the early and unpredictable dave who used the whole neighborhood as his stage. david letterman turns 67 in a few days.

he has been doing his show on cbs for 21 years. the other broadcaster in the news today was boomer esiason. former nfl quarterback used his sports radio show to rip into new york mets second baseman daniel murphy for taking paternity leave for the birth of his first child. it meant that murphy who hasn't missed a game in two seasons missed this year's opening day. and then esiason took it a step further by saying murphy's wife who delivered via c-section should have scheduled that before the start of the season. another radio host, mike francesa, says they should have hired a nurse instead. but murphy, the new father of a young son, got the last word today. he said, quote, a father seeing his wife, she was completely finished. i mean, she was done. she had surgery and she was wiped. having me there helped a lot, to take some of the load off. it felt, for us, like the right decision to make. veteran parents will find this next story familiar even if they haven't quite thought about

grocery shopping in this way before. it's about the breakfast cereals that appeal to kids. cap'n crunch and all his colleagues, not only are all they at eye level. researchers at cornell have actually studied this. they find the characters on the box of adult cereals like wheaties look right at you while the characters on kid cereals boxes tend to look down at a slight angle, perhaps down where the kids' eyes are likely to be looking up at them. when we come back tonight, jenna bush hager with her father, the former president, in our first look at what's officially being unveiled tomorrow.

finally tonight, with great thanks to our friends at the "today" show, we have a preview of a new exhibit that will open tomorrow at the george w. bush presidential library in dallas. a display of paintings of world leaders by the former president himself, having taken up painting with something of a passion since leaving office. tonight, we get our first look from the former president's daughter, "today" show contributing correspondent jenna bush hager, who spent some time with her father at the library. >> reporter: congratulations, dad. this is pretty exciting. >> well, it's -- yeah.

who would have thought it? >> reporter: not me. >> not me. >> reporter: my father's been painting for two years. he started off with our family pets, moved on to landscapes, then familiar faces. >> i brought a painting for you. >> you did? >> yeah. >> did you paint that? look at this! >> reporter: the aspiring artist has expanded his portfolio and is making it public for the first time. >> i was a little reluctant to put them out because i'm not a great artist. i don't want people to think i'm a great artist. >> reporter: but you do take it very seriously? >> i paint a lot. because, as you know, i'm a driven person, and i want to get better. i want to learn as much as i possibly can so long as i'm able to paint. so i've studied art for the first time in my life. a whole new world has opened up. >> reporter: his new exhibit includes a self-portrait and paintings of more than two dozen other world leaders. >> vladimir putin, yeah, i met with him a lot during the presidency. i got to know him very well. >> reporter: have any of these leaders seen their portrait? >> they have not. >> reporter: not one?

>> not one. >> reporter: what do you think their reactions will be? >> i think they're going to be, wow, george bush is a painter. looking forward to seeing the stick figure you painted of me. i fully understand it creates a lot of amazement. george bush, painter? but it is -- it's a joyful experience. >> the former president with his daughter, jenna. our thanks to both of them. you can see those portraits of world leaders, the president's self-portrait and 43's painting of his father, 41, all of it tomorrow morning on "today." as for us, that's our broadcast on a thursday evening. thank you for being here with us. i'm brian williams. as always, we hope to see you right back here tomorrow evening. good night.

nbc bay area news begins with breaking news. right now at 6:00, a crime scene outside of a bay area walmart store after federal agents fire shots in that parking lot. good evening, and thanks for being with us. >> you can see, authorities are still in fairfield gathering evidence tonight, and they've been there since 2:45 this afternoon when the first shorts were fired. federal agents were trying to capture a homicide suspect when they ended up opening fire on a man with a gun.

fairfield police then shot a second person. they say that person was wanted for attempted homicide. no one is saying what condition the suspects are in, but none of the authorities involved in this were hurt. nbc bay area will stay on top of this breaking story and will bring you more information as it comes in. the family of a man shot and killed by san jose state police is speaking out. marianne fauf reis in san jose with talks about a coverup here. >> reporter: that's right. in fact, right now lori valadez is still out here in san jose with many of her supporters. as the signs say, she wanting justice for josiah, that is her 4-year-old son. and seesaws police are not telling the truth about how his father died. lori valadez says she still can't believe antonio low pedestrian