congratulations to him. nbc "nightly news" is next, and more bay area news at 6:00. good night. test an out-of-control van careens more than 50 feet off a highway near new york city's bronx zoo. seven are dead, including three children. tonight, what happened. the clinton factor. looking for help raising campaign cash. the president turns to a one-time rival. the murder mystery in china that has the u.s. tasking notice. accusations of a cover-up and a stunning downfall for a government power couple. extreme makeover, coming to a hospital near you, made with baby boomers in mind. and royal anniversary, the prince and princess bride, one and royal anniversary, the prince and princess bride, one year later.

-- captions by vitac -- www.vitac.com good evening. we start tonight with a horrific highway tragedy here in new york. seven people, including three children, were killed when their van went out of control and careened off an elevated parkway, landing onto the ground of the famous bronx zoo. it happened on a clear and dry afternoon, and at this hour police are still trying to piece together how it all happened. michelle franzen is in the bronx tonight with the details. michelle? >> reporter: visitors and workers were not affected by that accident. police say the van landed in an area in a nonpublic area from in this park. that van had seven members of a family, including a toddler inside, out for a sunday drive, police say, when tragedy struck.

four adults and three children plunged to their deaths sunday after officials say their out-of-control van flipped over a guardrail of a raised parkway in new york city, and landed in the tram yard section of the bronx zoo. >> units arrived on the scene, and they found a vehicle upside down with occupants inside the vehicle. >> reporter: the victims, authorities say, are a family. one man, three women, and three girls between the ages of 3 and 15. investigators looked over the wreckage in the rugged terrain at the accident scene, a remote section of the zoo far away, officials say, from animals and visitors who were never in danger. >> pd came in with their dogs and did a search and helicopters were using their thermal imaging camera to see if they could pick up any heat inside the grounds. >> reporter: the initial investigation shows skid marks on the road leading officials to believe the driver of the van was traveling at a high speed at the time of the accident.

>> the driver may have struck a jersey barrier, and reacting to striking that barrier, the driver makes a severe turn. >> it hit something that caused it to become airborne. it fell 100 feet from the overpass and laded upside down when it hit the ground. >> reporter: it is the second accident on the raised bronx river parkway in less than a year. last june an suv plunged off the road near the same area after hitting an divider and injuring two people. city officials say they will ask agencies to review safety issues on the parkway. meanwhile, new york's mayor focused on offering his condolences, saying, our thoughts and prayers are with the family at this tragic time. a tragedy also being felt by emergency workers. >> sometimes you come upon events that are horrific. and this is one of them. >> reporter: investigators say they do not know where the family was headed at the time they were on the road. and they are not releasing the names of the victims. they will notify all relatives. >> michelle franzen, thanks.

now to a story that was just breaking as we came on the air last night, a deadly, fast-moving storm in the nation's heartland. high winds took down a tent after a cardinals game in st. louis. one person was killed, 100 more were hurt. and it's just the start of the severe weather season. nbc's katy tur is in st. louis for us tonight. >> reporter: a moment of silence at busch stadium this afternoon. cardinals fans reflecting on a night of violent weather that left this party tent hanging mangled from the railroad tracks. witnesses say the wind came in like a freight train, 50-mile-an-hour gusts that lifted the tent and all that was inside of it right into the sky. >> some girl was laying on the ground. her head is busted open bleeding. her fiance is saying get me a bar rag. i just took the shirt off my back. cover her head up with this. >> reporter: within a matter of

seconds, more than 100 people lay scattered by the impact instantly turning the unharmed partiers into paramedics. >> that's the beautiful thing, people rising above what they thought they could do. >> reporter: art randall owns the bar. he fought back tears through bloodshot eyes this morning remembering how he tried but failed to save 58-year-old alfred goodman. >> you second-guess everything. what could you have done here or there. did you do enough? >> reporter: wild wind and rain, pounded the nation's heartland. racing was suspended for 50 minutes at churchill downs. hail fell like an assault from above. >> in the change of seasons as we go from winter into spring you have the differences in the air masses and they clash and that leads to the potential in some cases for large hail. >> reporter: back in st. louis, the city's director of public safety was surprised that ultimately it wasn't so much worse. >> the severe and violent

weather event that lifted up this tent, it's important to realize that tents by their nature are temporary structures. they're not intended to provide shelter to people in severe weather events. >> reporter: and certainly people inside the tent were taken aback by the force of those winds. as for the 58-year-old man who died, there are conflicting reports tonight as to what actually caused his death. the owner of the bar tells me paramedics told him it seemed like he was struck by lightning. but officials can't confirm that to us at this hour. lester? >> katy tur tonight, thank you. to presidential politics now. four years ago, then senator obama was locked in the intense primary battle with senator hillary clinton. her husband campaigned tirelessly on her behalf. at times issuing harsh criticism of her opponent. but what a difference four years makes, as tonight the president turns to bill clinton for support to defeat mitt romney. we get that story now from nbc's peter alexander. >> reporter: headlining a private democratic fund-raiser

in suburban virginia tonight -- >> you're in good hands. >> reporter: -- one of the most powerful and until recently unlikely partnerships in politics. president barack obama and former president bill clinton. four years after the bitter primary battle that pitted them against one another. >> i don't think i'm that bad. >> you're likable enough. >> thank you so much. >> reporter: the relationship between the obamas and clintons has warmed. >> hello! >> reporter: the obama campaign helping hillary clinton pay off her 2008 financial debt. her husband increasingly vocal advocate for mr. obama during an already sharp general election fight. even appearing in this new ad touting the president's decision to order the killing of osama bin laden. one year ago this week. >> he took the harder and the more honorable path. >> reporter: but that has angered mitt romney supporters who blame president obama for using the raid as a political weapon. >> it's something that was a unifying event for all americans. an event that governor romney

congratulated him and the military and the intelligence analysts in our government for completing the mission in terms of killing osama bin laden. and he's managed to turn it into a divisive partisan political attack. >> reporter: obama campaign advisers argue the successful campaign to hunt down the al qaeda leader is fair game. >> just a few years ago, president obama, then a candidate, said in a speech that if we had actionable intelligence of a high-value target in pakistan we would go in and get that high-value target. mitt romney said that was foolish. he wouldn't do such a thing. that he wouldn't move heaven and earth to get osama bin laden. >> reporter: meanwhile, the last significant obstacle to romney wrapping up the republican nomination, newt gingrich will officially withdraw from the race this wednesday here in washington. >> reporter: mitt romney returns

to the campaign trail in new hampshire tomorrow, his second trip to the state in a week. president obama and vice president biden have been there five times in the last five months, lester, with just four electoral votes at stake. it gives you how close both campaigns in this fall's election will be. >> peter alexander in our washington newsroom tonight. thanks. while the debate continues in washington, president obama and members of his national security team are speaking out about the raid in exclusive interviews with brian williams for this week's "rock center." the president reflects on the tense moments and that now iconic photo snapped inside the white house situation room. >> there you are. >> here i am, sitting right here. >> that's an intense look on your face. and everyone is intently watching that screen. >> this is -- if i'm not mistaken, pete, this picture was taken right as the helicopter was having some problems. but you may not remember -- that's what it feels like.

because i remember hillary putting her hand over her mouth at that point. there's silence at this point inside the room. >> when you look at it, what does it conjure up inside you? >> well, that's the way i usually look when my husband drags me to an action movie. what it conjures up is all of the emotions that were running through my and every other person in that small group. it was just an extraordinary experience. and a great privilege to be a part of. >> you can see brian's full interviews this wednesday night on "rock center" 9:00, 8:00 central right here on nbc. the plan to raid osama bin laden's compound was well in motion when president obama took the stage at last year's white house correspondence dinner. only he knows what secrets may have been on his mind this year. but once again last night he directed plenty of zingers.

mike viqueira has that story. >> reporter: experts agree the coming campaign will be brutal. but before the nastiness, a little levity. >> it's great to be here this evening in the vast, magnificent hilton ball room. or what mitt romney would call a little fixer-upper. >> the occasion, the annual white house correspondents dinner. president obama got in a few light-hearted jabs at mitt romney. >> we also both have degrees from harvard. and i have one, he has two. what a snob. >> it's been said that washington is hollywood for ugly people. but for just one night each year, those two worlds collide. they call it the nerd program. -- prom. over the years the dinner has morphed into a major schmoozefest of glamour and glitz, capped off been the dinner itself where the president's bully pulpit becomes a night at the improv. >> four years ago i was locked

in a brutal primary battle with hillary clinton. four years later, she won't stop drunk texting me from cartagena. >> last night no one was spared. >> i had a lot more material prepared, but i have to get the secret service home in time for their new curfew. >> mitt romney wasn't there, but the president got as good as he gave. >> there's terms for guys like president obama, probably not two terms, but -- >> this year, dogs were a theme. from ughy -- >> can we show the ad real quick? >> to shamus. >> to join mitt romney in sending a message this november. i'm an american. and doggone it, i ride outside. >> if the experts are right and the campaign does turn bitter, last night may have been the last chance for a good laugh. nbc news, the white house. when "nbc nightly news" continues on this sunday, a murder mystery half a world away

that has the u.s. government paying close attention. and later, the new e.r., how hospital emergency rooms are being redesigned for america's aging boomers.

there's still no official word tonight about a blind chinese activist who made a daring escape from house arrest. chen guangcheng is possibly in u.s. protection possibly in the american embassy in beijing. neither the united states nor china have commented on the case. this is playing out just days before secretary of state hillary clinton is scheduled to visit china. and it's not the only high-profile incident that has the u.s. concerned. and china's communist government on edge. the leadership is being shaken by a scandal that has uncovered corruption at the highest levels

and perhaps even murder. nbc's chief foreign affairs correspondent andrea mitchell has more tonight. >> reporter: it is a chinese power struggle that reads more like a tabloid sex and murder mystery. communist party boss bo xilai. accused of corruption. >> undoubtedly the largest political earthquake to hit the chinese leadership in the last 20 years. >> reporter: and his wife, suspected of arranging the murder of a british businessman neil haywood who worked with her husband and may have been her lover. haywood found dead at this hotel and was cremated within hours before an autopsy could take place. the british government is even being accused of letting china cover up the case. >> we did offer to hold an investigation. >> reporter: it is a stunning downfall for a power couple who traced their roots to the early leaders of the communist party. >> the public started to

question, well, if bo xilai who was a corruption-fighting, gang-busting son of a revolutionary hero, is this corrupt, what does it say about the rest of our top leadership snrz >> reporter: adding to the scandal, the couple's son. educated at tony british schools, now at harvard's kennedy school. scandalizing the family with playboy lifestyle. >> what seems unusual, or at least not the norm is the degree to which he flouted his privilege in perfectly observable ways. >> reporter: corruption is widespread among chinese elites. but never talked about publicly. what may have sealed both fates is an even worse crime in the eyes of party leaders like the president. allegedly wiretapping their phones. >> if half the allegations against the bo family, not just him but his wife as well, prove to be true, it would suggest

that corruption goes right up to the top. >> reporter: for the u.s., anything that threatens the succession to china's next leader means trouble. so this is one scandal that the u.s. and china both wish would simply go away. andrea mitchell, nbc news, washington. we're less than three months now until the start of the olympic summer games in london. today we're learning new details about the intense security measures being used to protect that city and millions of visitors. residents of an apartment building in east london have been told that surface-to-air missiles could be placed on their rooftops during the games. up next here tonight, the new e.r., kinder and gentler for an aging population.

we're back with a fascinating sign of the times. as the population ages, putting greater demands on health care, some hospitals are responding with an innovative idea. emergency rooms tailored for the needs of older people. our chief medical editor dr. nancy snyderman has the story

tonight. >> reporter: while will turner is in the hospital, he's still in good spirits. >> that's wonderful. these cameras are unbelievable. >> reporter: texting his kids to let them know he's okay after being rushed to the energy department short of breath. >> it was a completely different experience than i've ever had before. >> reporter: different because this tech-savvy senior is in the new geriatric department spearheaded by physicians, including dr. ballman, whose grandmother was sent to a regular energy department after breaking her pelvis. >> it's frustrating that no one seemed to be paying attention to her, that she was kind of lost in the shuffle. >> we have 70 million baby boomers who are going to be turning age 65. those baby boomers have increased health care needs. and the emergency departments have to be ready. >> reporter: this is a new trend. getting to an aging population of americans, and improving their medical care in the

emergency room. and they're doing it by catering to the specific needs of baby boomers and their parents. >> just like a pediatric unit, trying to meet the needs of the kids. we're trying to figure out the things that would better serve the population. we are getting a boomer book cart. >> reporter: fully equipped with eight beds and six exam rooms, it's designed to have less noise than a typical e.r. >> there's no metal against metal sound like usual with curtains. >> reporter: non-skid floors, rails along the walls and artificial skylights that change with the time of day to prevent confusion. >> hello. >> reporter: volunteers are on hand to interact with patients. and it's what dr. ballman called the geri pad so patients can listen to music, ask for food. and have two-way video conversations with nurses. >> they say thank you 20 times a day. every time i pass their room or bed, they are very grateful. >> reporter: 94-year-old turner is among those previously overwhelmed by his experience.

>> at my age, you've been in a few emergency rooms. and nothing has equaled the person-to-person attention that you get here. >> reporter: dr. nancy snyderman, nbc news. more than a decade since the 9/11 attacks took down the twin towers, tomorrow the world trade center is set to reclaim its place as the tallest skyscraper in new york city. when workers began the 100-floor tomorrow, it will make one world trade center just over 1,250 feet high, just slightly taller than the empire state building. it's not expected to reach its full height of 1776 feet until next year. when we return, a royal marriage one year later.

finally tonight, the duke and duchess of cambridge better known as william and kate celebrated their first wedding anniversary today. yes, it's already been a year. from london, nbc's keir simmons looks at how they've settled into a life both royal and down to earth. >> reporter: it was a friend's wedding for kate and william. a year ago no need for umbrellas on their big day.

a year in which kate has won prize for herb royal debut, her kindness to children particularly noted. britain would love it if these two were expecting their own little one. what a year they've had. a wedding watched by billions. earning their country millions in tourism. >> they're unbeatable. they're showing everybody what to do and how to do it. >> reporter: they drew crowds of thousands during trips to canada and the u.s. what many people seem to adore about the duke and duchess of bridge is they are royals like real people. she's a style icon who buys many clothes in bargain stores. and at a hospice, kate wrote to one little boy, a personal letter. >> perhaps in this world of celebrity obsessed red carpet fever, it's quite nice to have a rising star who isn't a showoff. >> reporter: her confidence has grown visibly with solo appearances while william is away in the faulklands and her first public speech.

>> i'm really sorry william can't be here today. he would love it here. >> reporter: now he's back, and even after a year on the world stage, they still cook dinners and watch movies in their remote cottage in wales, a world away from the pomp of their big day. this time last year the sun shone on kate and william's wedding. lucky for them their not getting married this week, it's pouring rain in london. when they move into kensington palace next year, they're hoping they'll be blessed again with a new arrival. unlike princess diana, kate will not be put under pressure to begin having children. >> i believe they both want to start a family, but in their own time. >> reporter: after all, their first 12 months have already been truly a royal year. nbc news, london. that's "nbc nightly news" for this sunday. don't forget "dateline" tonight. brian williams will be here