the clock is ticking as rescue crews dig for survivors in kolkata, india, after a busy overpass collapse. and in the u.s., the president meets world leaders to talk security, and there are also growing concerns about a nuclear isis. also ahead this hour, angry protesters on the streets of france clashing with police, throwing bottles, setting cars on fire. we'll tell you what that's about. >> we want to welcome our viewers here in the united states and around the world. i'm george howell. >> and i'm natalie allen. thank you for joining us. we're live in atlanta. this is "cnn newsroom."

and we begin with the u.s. presidential race and the next big electoral contest on tuesday in wisconsin. there has been a big shift among the republicans and ted cruz is leading in that state. >> that's right. in fact, the fox business network survey released on thursday shows ted cruz with a 10-point lead over donald trump, 42 to 32%. only 19% of likely republican wisconsin voters support john kasich. this is the second poll this week with cruz on top. >> this comes as a very well funded group supporting kasich released a scathing cruz attack ad. >> many just call him lyin' ted. lied about ben carson to steal a win in iowa. lies about being the best for the gop when polls show he can't even beat hillary clinton. his tv ad about john kasich?

lied. stations had to pull it off the air. if ted cruz's mouth is moving, he is lying. >> well, part of a half million campaign ahead of wisconsin's tuesday primary. kasich said he had nothing to do with the commercial and is distance himself from it. >> meanwhile, democratic presidential candidates hillary clinton and bernie sanders are looking ahead to new york's primary on april 19th. >> they both campaigned in state thursday where clinton helolds 12-point lead. but she is not taking her home state for granted. >> reporter: now playing in new york, hillary clinton -- >> he goes around telling young people he is going to give them free college. >> reporter: versus bernie sanders. >> secretary clinton has supported virtually every one of these disastrous trade agreements. >> reporter: the democratic rivals duelling on their home turf for a whopping prize of 247

delegates, i grew up in brooklyn, new york. >> reporter: their fight is also now reinvolving around that other new yorker, donald trump. >> just yesterday, donald trump said women should be punished for having an abortion. >> reporter: both democrats seizing on his comments about how women should be punished for seeking an abortion. he recanted his words, but that did little to stop the firestorm. sanders tweeted "your republican front-runner, ladies and gentlemen. shameful." by now the clinton campaign had hoped to be focusing on trump and republicans alone. but at a rally not far from her chappaqua home, clinton found herself tangling with sanders supporters. >> she wins, we lose! >> oh, i know, the bernie people came to say that. >> reporter: as clinton loyalists rally to her aid. she had the last word. >> what i regret is they don't want to hear the contrast between my experience, my plans, my vision, what i know i can get

done and what my opponent is promising. >> reporter: but as she shook hands and environmental activists clearly got under her skin. as captured in this video posted by greenpeace and circulated by the anti-clinton superpac. >> i am so sick of sanders campaign lying about this. sick of it. >> reporter: it's a stark reminder the democratic primary is also boiling hot. in wisconsin, which votes tuesday, sanders leads clinton by four percentage points. here in new york, clinton holds a 12-point lead. but she is not resting easy. even dispatching former president bill clinton to union halls across new york city. before a knighttime rally in the bronx, sanders stopped in pittsburgh. >> what an extraordinary turnout. >> reporter: he lashed out at clinton's support for trade agreements and ties to wall street. >> i just don't know why wall street has not invited me to speak before them. and i got my cell phone on. i'm waiting for the call. >> reporter: of course, wall street and income inequality two of the issues that are central

to this democratic primary fight, and certainly here in new york. now one of the questions that has been asked about the sanders candidacy is can he attract a diverse set of voters. at this rally behind me in the bronx, it is one of the most diverse rallies we have seen. for tonight at least the awer is yes. the sanders campaign believes that going forward, the states play well to their strengths. they can attract a diverse set of voters. that's why the new york primary on april 19th is so important as to how long this democratic race will go. jeff zeleny, cnn, new york. we are also following that major nuclear security summit in washington. leaders from japan, from south korea and the united states are pledging to stand together against north korea's nuclear ambitions. >> u.s. president barack obama also met chinese president xi jinping. china is key economic ally to north korea and beijing has been criticized before for not doing enough to enforce western sanctions against pyongyang.

>> of great importance to both of us is north korea's pursuit of nuclear weapons, which threatens the security and stability of the region. and president xi and i are both committed to the denuclearization of the korean peninsula and full implementation of u.n. sanctions. we're going to discuss how we can discourage action like nuclear tests that escalate tensions and violate international obligations. >> alexandra field is in brussels where there are growing concerns of terrorism going nuclear. all right. alexandra not ready for us yet. she can't hear us. we're going to go to paula hancocks. she is in seoul, south korea. she has been watching the meetings that are under way in washington. and she joins us now. paul lab, hello.

>> hello, natalie. well, yes, those meetings really have been focusing on north korea when it comes to the meeting between president obama and the japanese and south korean leaders. and just in the past few hours also we've heard from the joint chiefs of staff that north korea has fired one more missile. this has been happening fairly frequently over recent weeks. a surface-to-air missile from the east coast of the korean peninsula into the sea. so certainly this is one of the things that leaders will be watching. they are focusing on whether or not the sanctions that are being taken against north korea recently will be fully implemented. certainly all sides want to see that, president obama saying he wants to restore a sense of stability and peace to the region. all three of those leaders agree with that. and also, president park geun-hye of south korea saying she wants to make north korea understand that it cannot survive without giving up its

nuclear program. natalie? >> what do we expect as far as these sanctions continue, paula, what more perhaps can be done to see if they're having an effect on north korea? >> well, i think the accepted person responsible or country responsible is china. the fact that they share that very large border with north korea, the fact that most trade goes through china, and the fact that much of the smuggling in the past has gone through that border. so clearly, it's heavily up to china, not solely, to implement those sanctions, all cargo in and out of north korea now must be inspected according to the sanctions. and we have heard from president xi through the xinhua state-run news agency in china saying that he is stressing all parties should fully and strictly carry out the u.n. resolution, also

calling on all sides to refrain from any rhetoric or action that could increase tensions. according to xinhua, the president is very clear that he wants full implementation of these sanction. certainly beijing surprised many by even agreeing to the sanctions in the first place. but if fully implemented, according to experts that. >> could have an impact on potentially on the missile and nuclear program. but of course, it will be until the end of the year, they say, until we even know if they are having any kind of an impact. natalie? >> thank you, paula hancocks for us in seoul, south korea. and we'll talk with alexandra field in brussels soon here when we reestablish contact. in kolkata, india, a rescue operation is under way there. rescuers are still digging through rubble. they are searching for people who still could be trapped under a highway flyover that collapsed. at least 24 people died there. 80 others were rescued from the debris. it is still not clear why that

overpass, which was under construction, collapsed on thursday. >> a lot of people got buried in it. this market off this area. so basically, we are trying to remove the debris and try to, you know, recover the bodies. because i don't think many people are alive over there. removing the boulders, whatever the debris are, trying to remove them. we're pulling out cars from the debris and helping these people do their job. >> it is a desperate search there. cnn's ravi agrawal is live with developments. you are live in the middle of everything that is happening there. can you set the scene for our viewers and tell what's is happening around you. >> reporter: hi, george. we're now well into about 24 hours since the bridge first collapsed. you just heard some debris being unloaded behind me on one of the trucks. a lot of the disaster relief

sort of authorities here are saying that they're not very optimistic anymore about finding any more bodies in the rubble dead or alive so far as you said about 18 bodies have been rescued from the rubble. and really, the scope and scale of the devastation here is quite immense. this was an overpass, what kolkatans call a flyover. that cut through a very busy part of kolkata. and about 100 meter stretch of that overpass just gave way 24 hours ago. and it collapsed on a number of people who were working below that. people who were selling foodstuffs, other kinds of things, vendors, drivers there were cars. you can still see, if i point to the overpass over there, you still see that there is a truck crushed underneath that. there are other cars around that

that are still trapped in the rubble. very difficult to get to those cars. and disaster relief authority here is have been working for about 15 hours now. but they're running out of hope. >> the prime minister narendra modi tweeted that he was, quote, shocked an saddened. and the company that actually built that flyover, an executive described it as an act of god. but when it comes to the why and the how of this bridge coming down, this overpass coming down, who is pointing the finger at who at this point? >> well, it's turning into a political blame game of sorts. the party in power, they showed up a couple of hours after the bridge collapsed. and they made every effort at least publicly and visibly to try to get disaster relief on

board. they're saying now that we didn't commission this project. it was commissioned by the previous government. of course, the previous government says it has nothing to do with it. meanwhile, the construction authority says that it was an act of god. so a lot of fingers pointing in different directions. some of it might also be because next week here in kolkata, we are going to see state assembly elections. these are crucial elections that decide who is going to run this state. it also has a national impact in terms of how many seats the ruling party gets in power in new delhi. so very coincidental elections. and a lot of fingers being pointed here. really, this is the scene of immense devastation. and this is where rescue efforts are ongoing right now. and hopefully, they might be able to rescue more people. >> so much happening there behind you. very active scene. and certainly the hope is that those teams there are able to

find anyone else trapped under that debris. ravi agrawal live in kolkata, thank you so much for your reporting. and we will stay in touch. we want to turn now back to the nuclear summit we were talking about a moment ago. and a few hours, world leaders will have a special session on the nuclear ambitions of isis militants. u.s. president barack obama met with his french counterpart on thursday. the two countries pledged to step up their efforts to fight terrorists. >> this is obviously an occasion in which we are deeply concerned about nuclear security, making sure that nuclear materials don't fall into the hands of terrorists. but in the wake of brussels attack, with our memories of the tragedy in paris, we have not only great urgency around the nuclear issue, but eliminating generally the scourge of terrorism. >> so there are concerns of --

growing concerns of terrorism going nuclear. and our alexandra field joins us live from brussels, belgium with more about this. a very serious and terrifying thought there, alexandra. >> sure, natalie. it is serious. it is concerning. what it isn't, however, is new. and that is sort of the message you get when you speak to official here is in belgium. they say look, they know isis has an interest in nuclear sites. they know that militants are interested in procuring radioactive materials. what they'll tell you is for the last few years they've been stepping up efforts to try to secure the sites and cut off potential access to the steelersteeler to sites. now following the brussels attacks, they say they're trying to keep the highest level of security in place. and they're also carefully watching and closely monitoring anyone who could have access to those facilities or the materials inside. this is the path of devastation,

death left behind by brussels bombers and brothers ibrahim and khaled bakroui. they attacked the airport and the metro. but had they considered even more? did the bakroui brothers have nuclear ambitions? did they intend to build a dirty bomb? those are the kinds of questions that investigators are asking after recovering video from a safe house connected to the terror cell that carried out the attacks in paris and brussels. a senior belgium counterterrorism official tells us the video shows ten hours worth of surveillance on the home of a nuclear researcher. at times you can see him and his family going into and out of the house. analysts suggest that the video might point to some kind of plot to kidnap the official in order to gain access to radioactive material. >> it's absolutely not feasible. it was kind of phantasm in their brain, in their head. >> the fact that this video was even made, how alarming is that to you?

>> it is alarming. but it's very alarming for the person targeted by the terrorists. >> reporter: could a terrorist realistically carry out an attack by kidnapping one employee? >> no, i don't -- you could kidnap a person. but that doesn't mean that -- it's not that simple that you can just hold a gun to a person's head and force your way into a nuclear facility. there is multiple barriers, identity check, physical barriers that prevent someone from getting in in that kind of way. so i don't think that's very realistic. >> reporter: in 2014, someone inside the nuclear power reactor in belgium sabotaged a nonnuclear part of that plant. also that year, a terrorist opened fire on a jewish museum in brussels. after those incidents, security around belgium's nuclear facility was stepped up, according to belgium's federal agency for nuclear control. following the paris attacks, armed guards were assigned to

protect facilities in line with practices at other nuclear power plants in europe. and in the days after the brussels bombings, four employees had access to various facilities taken away. part of a policy of constant monitoring. some of the measures recognized in a recent report from harvard's school saying belgium has made some of the most substantial nuclear facility improvements in the security. the country had been criticized for failing to strengthen nuclear security southeastern. >> no one is suggesting that belgium's nuclear security is compromised or there are a set of threats they can't deal with. really, whether the security in belgium is as good as it can possibly be. >> reporter: investigators might never know whether the bakroui brothers intended to build a dirty bomb or what methods of construction they may have considered, only the damage left behind. >> and natalie and george, in terms of that decision to revoke the access of four employees in

the aftermath of the brussels takes, the federal agency for nuclear control says that decision wasn't necessarily connected to the attacks themselves. they say this is a process that is continually ongoing. they're always watching and evaluating employees. however, they do say that in one of the cases, one of those four cases, that employee's access was revoked after colleagues reported that this person had what was described as an inappropriate or an unusual reaction to the images of the attacks that the whole world was seeing on that morning just last week. natalie, george? >> curious. all right. alexandra field for us this in brussels. thank you. >> you're watching "cnn newsroom." still ahead, anger boils over into violence in france as these protesters tell the government its plans for labor reform will do more harm than good. full details straight ahead. rough night?

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but protesters argue it's all at the expense of workers' rights. the city of lights illuminated by flairs. a major european landmark off limits as thousands of people filled the streets of paris thursday in protest over labor reform proposals. riot police and tear gas in the city as rallies turned ugly, nationwide more than 100 people were arrested after clashes with law enforcement. the french government says it can boost employment and the country's economy by making it easier for companies to lay off workers and reduce hours. these demonstrators say that's nonsensical. >> translator: it's ridiculous. we're moving backwards year after year. reform after reform. it's always in the wrong direction. a reform nowadays has a completely negative connotation. when i was young, a reform meant something good. it would improve things. but today it's the opposite.

>> translator: we're here to fight for our rights. otherwise we'll lose everything. for us who are quite old, it's okay. but the worst is for our children and grandchildren. they'll be left with nothing. >> reporter: protest organizers claim 1.2 million people turned out to voice their disapproval of the measures which would also compromise france's statutory 35-hour workweek. oficial figures put attendance closer to 400,000. but what isn't debatable is the strength of feeling among sections of french society about the possible changes which are due to be voted on within weeks. french president francois hollande says he won't stand for reelection if he can't reduce unemployment to below the current 10%. but his detractors argue his methods will do more harm than good. >> translator: we've had enough. if it's hollande who pretends to represent the left. the future for the youth when we see our youth in universities having to sit sometimes on a floor. even my dog has a blanket to lie

on. it's not okay. the youth are told to study for years, but what for? what for if it's to end up unemployed or to work in a supermarket? >> reporter: strikes across the country disrupt the transport and forced the closure of schools in addition to france's most famous attraction. a towering challenge for a president and a government already under intense pressure. the ex-wife of the world's most wanted man is speaking out. the new details we're learning about the leader of isis. that's coming up next here. you're watching "cnn newsroom."

welcome back to our viewers here in the u.s. and around the world. you're watching "cnn newsroom" live from atlanta. i'm natalie allen. >> and i'm george howell. here are the headlines we're following. this hour, emergency officials in india say at least 24 people are confirmed dead after a highway overpass collapsed on to a busy marketplace in kolkata. 80 others were rescued from the debris. it is not clear, though, why this overpass, which was under construction, collapsed on thursday. a belgian court has ordered the extradition of paris terror attack suspect abdeslam to france. he came the most wanted man in europe after the november attack that killed 130 people. police in belgium captured him two weeks ago. it's unclear when the transfer will be carried out. at least 14 people are dead after suicide attacks in two separate areas of northern iraq. officials tell cnn six kurdish

police were killed in makhmour in which a car bomb exploded. another bomb near the persian gulf camp. eight people were killed and isis has claimed responsibility for the attacks. we are learning new details about the leader of isis, abu bakr al baghdadi. his former wife gave an interview about their brief marriage and said she was shocked when she found out what he had become. >> in fact, she even described the isis chief as a, quote, family man. cnn's brian todd has this story for us. >> reporter: a new warning from top u.s. officials to the terrorist leader of isis. we'll find you. >> abu bakr al baghdadi's days are numbered. >> reporter: president obama's anti-isis envoy says abu bakr al baghdadi is most likely hiding in the isis stronghold of raqqah, syria. could u.s. intelligence just picked up crucial information on al baghdadi from his ex-wife? saja al dulaimi has just given a videotaped interview to the cnn

swedish affiliates suppressen. >> why did you leave? >> translator: i wasn't happy. >> did you love him? >> translator: no. >> reporter: al dulaimi says it was an arranged marriage. she was married for a few months in 2008. at that time he was a university lecturer who went by mohamud. she said she didn't know he had terror connections at the time, even though baghdadi had been held by the americans earlier. >> it is conceivable he had been living a double life and the fact he didn't tell her anything and was mysterious was because she was not privy to the real side of him. >> reporter: saja al dulaimi says she was shocked when she later found out her ex-husband is the most wanted man in the world. baghdadi is said to have sexually assaulted american captive kayla mueller repeatedly according to u.s. officials. but in her interview al dulaimi describes him as, quote, a

family man. >> he was the children's ideal father. the way he was with children, he was a teacher. you know how teachers are. he knew how to deal with children better than how to deal with the mother. >> did you dare have discussions with him? >> no. >> why not? >> he has a mysterious personality. >> reporter: she says their relationship was shallow, that baghdadi would boss her around. al dulaimi says his other wife, her.he married first, resented after just three months of marriage she left him, but not before becoming pregnant with the terror leader's now 8-year-old daughter. cnn is not revealing her face. analysts believe she may be in danger. >> i think that these children are very much in danger. if not just from agents of al baghdadi who might try to kidnap them, also people who are opposed to isis who may try to use them against al baghdadi.

>> saja al dulaimi's other children are from other husbands. as for the 8-year-old daughter she had with al baghdadi, she said the terror leader did tell her he would take the child back if she remarried, which she has. u.s. intelligence officials aren't commenting on any insights they may have gotten from the interview. but one terror official told us the account of al baghdadi as a bad husband should come as no surprise. brian todd, washington. the legal fight between apple and the fbi over the terror smart firm has put an israeli tech firm into the spotlight. >> neither that security company nor the fbi are talking what could be a big break in a crucial investigation. oren liebermann is in tel aviv for us. >> reporter: four months after the san bernardino terror attack, the iphone 5 c remained a critical but inaccessible piece of evidence. an ugly legal battle between the fbi and apple suddenly ended when the fbi found a different way to get into the iphone.

an israeli newspaper cite industry sources that the company that did the work is called celebrite. their offices are behind me. neither the fbi nor cellabright will comment. but they specialize in mobile device data extraction and description, phone hacking. and that's exactly what the fbi needed in this case. we reached out to cellabrite and the fbi repeatedly. they didn't return our calls and the fbi wouldn't comment. the fbi said only that they used a outside company. but the fbi signed a $200,000 contract with cellabrite the same day the fbi announced it had gained access to the content in the shooter's phone. shares of the parent company soared. at a tech conference in 2014, cellabrite's director told cnn about their work. >> we allow a very deep and

detailed access to a lot of information that is on the mobile device. and then it allows them to deduct who did what when, which is the essence of any investigation when you look at it. >> reporter: their technology isn't just a hack on an iphone. critics say it's a hack on privacy. he says his company has been challenged in court. >> we've got to make sure that whatever you bring into court can stand there and can stand any cross-examination. there are very strict rules and guidelines with most of the countries, and we need those. we need those. to the best of our knowledge. >> to learn more about mobile device security, we meet michael, a mobile technology expert at checkpoint, an israeli cybersecurity firm. what are the weak points of an iphone or any other mobile device that you can access the phone through? >> when you connect the cable to the phone and you can abuse all kind of protocols, the iphone can communicate with the laptops. and by hijacking or manipulating those protocols, you can

actually unload the phone. >> if i give you my iphone or hand it to you, how long would it take you to hack this iphone? >> it would probably take me to hack your phone when it's in your hands rather than you give me the phone. it's much easier to conduct a social engineering attack, something you cl click on and install something on your phone rather than i would try to guess or break your pass code. >> this is the flip side of the startup nation. innovation used to build security now used to exploit vulnerabilities. is cellabrite the company behind the attack? they're enthusiastically touting its technology not long ago as now gone silent. oren liebermann, cnn, tel aviv. well, the southeastern united states is taking a beating from some violent weather. tornadoes, hail and flooding have been pounding parts of the reason there is one right there. >> that's right. the national weather service

says a suspected tornado was spotted near new hope, mississippi. a local emergency management official tells cnn there are reports of downed trees and roof damage, but so far no injuries. >> let's check in with our meteorologist karen mcginnis. this is your top story i would assume. >> it is. and the severe weather season is on us. and across the southeast, the violent weather is taking shape across the deep south. this is a multiday event. new hope is just about in this vicinity where you see this tornado icon. now the local national weather service offices will have to send out people. they survey the damage. they look at the extent of damage, the type of damage that is done. and then they give a value to that tornado, meaning enhanced fujita, 1 through 5. and so we'll look at this. but go ahead and take a look at the damage. this out of mississippi. new hope. there were downed trees. there were downed power lines. and amazingly enough, no reports of any injuries from this touchdown. you can imagine just how frightening it was as this came

towards the evening hours. but not just there, also at priceville. this in northern alabama. where some of that severe weather is now shifting a little farther to the east and to the south. here is huntsville. here is birmingham, sort of just to the south of huntsville, alabama. here is priceville there is the cell that was the problem maker that produced the tornado there. also, no reports of any injuries. amazingly enough. but numerous reports of very high water, and now we shift that focus a little bit further towards the east. and some reports we have just gotten another update on the computer models. and we were looking at 4 to 6 inches just to the south of atlanta. now it looks like that has changed again. this weather system looks to be falling apart. that's not to say we wont see more in the way of severe weather, because we certainly could. and this should materialize on friday through the carolinas, south georgia, and then into the panhandle of florida and maybe even into alabama.

well, just when you thought spring was here, because we're seeing the springtime systems, here is a little clipper, because it moves very fast. that's the good news. the clipper is going to usher in much colder air. when you look at saturday and sunday, these temperatures are going to be well below normal. don't put away those coats and sweaters just yet. back to you guys. >> it's not a april fools joke, karen? >> no, it's not. that's the thing. april is fickle for sure. >> karen, thank you so much. award winning architect zaha hadid has died. coming up, her innovative designs that amazed and inspired people around the world.

tens of thousands of brazilians are showing their support for their embattled president dilma rousseff. they rallied in 17 states and the nation's capital thursday as

lawmakers consider a request to impeach rousseff. she says efforts to remove her from office amount to a coup. >> in the meantime, brazil's supreme court has dealt a temporary victory to her mentor, the ex-president there, luiz ignacio lula da silva. the justices removed the corruption investigation from a lower court judge who is seen as a crusader against graft. the u.s. centers for disease control is hosting a zika action plan summit on friday. their aim is to come up with a coordinated response to deal with the growing threat from that virus. >> cdc says active zika transmission has been identified in 39 countries and territories worldwide. a health alert was issue affidavit the first brazilian zika case was confirmed in may of last year. in south africa, scientists are working overtime in the only level 4 biosafety lab on the continent. but their mission to fight the

virus like zika also takes them to some very unusual places. david mckenzie has this report for us. >> reporter: the hazmat suits and respirators make for a difficult descent. it's much needed protection against what we could find in the cave below. we're following some of the world's most highly trained virus hunters in search of disease carrying bats. >> so they have to crawl through the narrow into the different chambers. because in each chamber there could be a different type of bat which could have different viruses. >> reporter: and in this cave, there are thousands. each one with the potential to carry rabies. marburg, perhaps even ebola. >> this is another male. >> reporter: some of the world's most severe but least understood viruses. >> even with ebola, there is not a direct link between the human outbreaks from the bats. we see some evidence in the bats and we see human outbreaks, but we can't say that bat caused the

human outbreak. >> so-so much is still unknown. >> a lot is still unknown. >> reporter: so they study diseases here in bat populations before the potential human outbreaks. >> otherwise you just react is all you do. a lot of people dead like we did in the ebola outbreaks. >> reporter: so if you just react, it's often too late? >> and you respond to that. so this is an adult. >> reporter: this isn't some remote cave. outside just miles away johannesburg, a city of four million. so close to human habitation, this type of monitoring and prevention is critical. >> we work in the most dangerous passages known to humans. >> reporter: disease detection that exists thanks to this, a fully enclosed pressurized safety lab, the only within of its kind in africa, with the highest level of precaution must be taken, researcher train for a year just to step inside. here they aren't surprised that the recent outbreak of zika, a virus once thought to be remote

and isolated. >> we have a global world. so these emerging viruses, well, we may find them here in africa, they may impact the populations here, the people here, or the animals here, and they may impact populations in other countries. >> so starting with this number that is on top. >> reporter: outside the cave, blood and saliva samples are taken, and the bats are marked before being released. back into an environment that seems increasingly primed for outbreaks. david mckenzie, cnn, south africa. >> quite an assignment for david there. >> yeah. one of the world's most innovative architects has passed away. zaha hadid is known for her unconventional sweeping designs that dazzle the eye and the imagination. >> they are indeed beautiful. the curve, the architecture just beautiful. hala gorani has a look at the incredible mark she made on modern architecture. >> reporter: zaha hadid's work can be seen in cities around the world. from manhattan to miami, morocco

and moscow. she was known for her curvy, dramatic and contemporary designs. among her most famous buildings the london aquatic center, built for the 2012 olympic games. the maxi museum in rome, this colossal cultural center in azerbaijan. and cincinnati's contemporary arts center. the design that jump-started her career and the first museum in the u.s. designed by a female architect. born in baghdad, she knew since she was a little girl that she was destined to build great things. >> i always wanted to be an architect. since i was maybe i don't know, 7, 8, 9, 10 years. i can't remember now. i think i saw a show in baghdad which intrigued me. >> reporter: hadid grew up in iraq, studied math in beirut, and left for london in the early 1970s to pursue her dream. she graduated from london's prestigious school of architecture and established her own firm in 1979.

she went on to design boundary-pushing structures all over the world. and not just buildings. hadid came up with furniture, even shoes. her critics described her as the lady gaga of architecture, and she won numerous awards worldwide for her work. most notably, in 2004, she became the first woman to be awarded the pritzker prize. architecture's highest honor. >> it's the wow factor. a fantastic day for me and it's a great deal for me. >> reporter: hadid said as a non-british woman in london, she felt like an outsider at times, but added this sometimes worked in her favor, helping her break ground in a male dominated field. >> i used to not like being called a woman architect. i'm an architect, not a woman architect. >> reporter: zaha hadid, a dame commander of the british empire and one of "time" magazine's most influential people. her legacy lives on within many

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and welcome back. the next big prize of the presidential election season is up for grabs next tuesday in the state of wisconsin. >> on the republican side, it is winner take all. cnn's zain asher tells us that's one reason why wisconsin matters. ♪

>> reporter: all eyes on wisconsin, famous for its beers, bratwurst and cheeseheads. descending on the badger state ahead of the april 5th primary. >> wisconsin is a battleground. >> reporter: with 42 delegates up for grabs, the stakes are especially high for republicans. ted cruz has picked up the endorsement of wisconsin's governor scott walker, himself an early casualty of the republican race. while former wisconsin governor thompson is backing john kasich. >> wisconsin is a very independent state. >> reporter: they're hoping to stop front-runner donald trump's momentum before the race heads to trump's home state, the new york primary on april 19th. on the democratic side, the 86 pledge delegates at stake are crucial to bernie sanders's hopes of making up ground on hillary clinton's big delegate lead. >> we think we do have a path toward victory.

>> reporter: wisconsin could also prove key in november's general election. while it's home to the republican leader in congress, speaker of the house paul ryan, president obama won the state in both 2012 and 2008. >> wisconsin is one of those states that you really don't know how the people are going to vote. >> reporter: and state officials are expecting huge voter turnout, saying they could see the state's biggest number of voters for a primary in 36 years. zain asher, cnn, atlanta. >> wisconsin on tuesday. we will have to wait and see. we thank you for watching this hour. i'm george howell. >> i'm natalie allen. remember to connect with us any time on twitter. "early start" is coming up for viewers in the u.s. . . .

donald trump and the republican national convention in a secret meeting. what went on? hillary clinton getting angry calling out bernie sanders for lying. and in a few hours, world leaders in critical meetings. can they keep nuclear weapons out of the hands of terrorists? welcome to "early start." i'm boris sanchez. >> i'm christine romans. it is friday, april 1st. april fool's day. you've been warned. 4:00 a.m. in the east. donald trump trying to explain why he told