lester holt who joins us for "nightly news " in rio. breaking news tonight. what did donald trump just say? controversy erupting as we come on the air after we hear what he said about hillary clinton, the judges and the second amendment. and violence. and babies in critical care being urgently moved after a potentially deadly bacteria is discovered. is it connected to the deaths of two infants? ferris wheel accident. children hospitalized after a terrible fall raising questions about safety. who's regulating all those rides? and golden statement. from an american champion caught up in a cold war with her russian rival, showing who's really number one, as all eyes turn to simone biles

in the gymnastic's finals tonight. "nightly news" begins right now. >> announcer: this is nbc "nightly news with lester holt" reporting tonight from the olympic summer games in rio. good evening from brazil and from baha olympic park at the start of another evening of competition after a very good day for team usa. we'll have more about the action here ahead. but we want to start here at home with donald trump and a potential new controversy simmering tonight after a remark that, at best, was a joke and at worst was an implied threat of violence. we'll let you here in a moment and let you decide for yourself. note that it comes as our new poll shows trump's efforts to regain lost ground have exposed a new weakness among what has been his strongest core of support. nbc's hallie jackson has late details. >> reporter: late today, donald trump under fire for this. >> if she gets to pick her

judges, nothing you can do, folks. although the second amendment people, maybe there is, i don't know. >> reporter: the clinton campaign believes trump's suggesting violence. quote, what trump is saying is dangerous. democratic senator chris murphy calling it an assassination threat. listen again. >> if she gets to pick her judges, nothing you can do, folks. although the second amendment people maybe there is, i don't know. >> reporter: trump's team argued second amendment people are, quote, tremendously unified which gives them great political power. >> reporter: you don't believe he was inferring any violence relating to hillary clinton? >> of course not. saying donald trump is right. if hillary clinton gets to pick her second amendment supreme court judges, there's nothing we can do. >> if he's suggesting violence against his opponent, i think

that's what most americans say we don't condone and should not be president of the united states. >> reporter: new signs the controversial candidate is in trouble with his base. sean voted for trump in the primary and won't back him in november. >> sometimes some things are better left unsaid. >> reporter: trump lost support with white men in the last two weeks as they begin to back hillary in stead. our online poll now showing a double digit slip among white member without a college education his most dependable source of support until right now. among all white voters with college degrees, clinton getting stronger in blue battle grounds donald trump needs to win. >> donald trump's drop in support among college educated white is is happening at the almost exact same time many moderates and businessmen are abandoning trump for clinton or someone else. that's not a coincidence. >> reporter: one of those republicans,

susan collins from maine who says she cannot vote for trump and trump's comments now rising to the level of the secret service telling nbc news tonight the agency is aware of those remarks. >> halle jackson tonight. a hospital has moved its newborns and looking into whether the deaths of two infants could be related. >> reporter: all nine infants at a neonatal care unit have been moved to other hospitals after the discovery of bacteria that can be deadly for fragile newborns. a hospital official says two infants in the unit recently died. >> there's been no clear cause

of death related to the infection itself. >> reporter: three of the nine patients tested positive of the bacteria, but none of them showed symptoms of the bacteria. it's called pseudomonas and it can be deadly for newborns who don't have hearty immune systems. >> it's a big deal when we find this in a n neonatal care unit because these infections can have grave consequences for the children. >> reporter: the centers for disease control says clinics and hospitals 6700 drug resist stand causing 240 deaths, mostly adu adults. two newborns died from it ten years ago at a los angeles hospital and it killed four infants in 2012 in the uk. hospital officials insist it was routine testing that discovered the bacteria, which they believe came into the neonatal unit through a water pipe. pete williams, nbc news, maryland. there was no end to the nightmare for thousands of travelers today as delta

airlines struggles to recover from a system outage that grounded planes across the world and today the airline cancelled another 680 flights. nbc's kerry sanders is at delta's largest hub in atlanta. good evening. >> reporter: good evening. tonight, delta can't say how many flights have been delayed but we do know the number of delta flights cancelled in the last two days now stands at more than 1600. tonight there are frustrated and exhausted passengers here in atlanta and around the world still trying to get from point a to point b, including a woman wearing her wedding dress. delta airlines says it has narrowed the problem down to a power surge that took out a computer module and the backup system also failed. lester. >> kerry sanders in atlanta, thank you. new questions are being raised about the safety of amusement rides in this country after something went terribly wrong at a county fair in tennessee.

three girls are hospitalized after plummeting from a ferris wheel, and it comes so soon after a boy was killed in a water park in kansas. we get more from nbc's gabe gutierrez. >> reporter: the ima images are horrifying. a ferris wheel basket overturned at tennessee's greene county fair. >> we have had a major incident at the ferris wheel. there's been at least three fall out. >> reporter: three children plunging more than 35 feet. >> there was some rocking, i didn't think it was such a big deal. most people rock it anyway. >> reporter: this accident follows the death of a 10-year-old boy at a water park in kansas. the national consumer products safety commission estimates 7,000 people went to emergency rooms last year for ride related injuries. there are no federal regulations for amusement rides and specifics vary widely across the country. 24 states have comprehensive government inspection and accident investigation programs. 11 states, including tennessee, have minimal requirements and leave oversight to the private sector. nine states have partial

oversight and six states have no regulations. >> we need consistent regulations, consistent standards across the board. we need these protocols and we need them now. >> reporter: the international association of amusement parks and attractions tells nbc news safety is its top priority, adding there's no evidence federal oversight would improve the already excellent safety record of the industry. the ferris wheel at the greene county fair was last inspected on june 21st. with no violations. third party inspectors were brought in today to look at all the rides. >> it looks, at this point, that it was a mechanical failure that caused this. >> reporter: tonight the rest of the fair is open, as investigators try to piece together what went wrong. a representative for the company that owns this ferris wheel says its thoughts are with the family of the three girls who were injured. they range in age from 6 to 16 years old and tonight the youngest remains in critical condition, lester. >> gabe gutierrez, thank you very much. let's move to rio de janeiro and it has been a big

day for team usa here, it could be a spectacular night as the americans look to make even more history. we're not going to report any results that haven't already been widely reported. but ahead of our prime time action, we can tell you, as expected, the american women's gymnastic's team was golden. this as the biggest names in u.s. swimming are getting set for giant races tonight. nbc's miguel almaguer has all the action for us. >> reporter: the american women keep setting the bar. >> it's critical, this combination. >> reporter: team usa led by simone biles, the smallest athlete with the biggest impact. today the first ever back-to-back team gold. moments ago, simone biles on the win. >> i felt like i would cry, but i'm too happy to cry right now, but it definitely feels like a dream. >> reporter: with the russians fighting to make the podium, their athletes face backlash from their doping scandal every

day. >> and you're hearing boos as team russia comes out. >> reporter: the bad blood came to a head last night. >> she is one controversial figure along with an entire country. >> reporter: russian yulia efimova mocked by lilly king before the start of the 100 meter breaststroke. >> you can really feel the tension in here right now. king exploded through the water and off the wall. the american beating the russian. striking gold, making the statement in the water and taking a stand out of the pool. >> we can still compete clean and do well at the olympic games and that's how it should be. efimova called the drama politics and the open hostility sad. tonight,michael phelps headlines the duel in the pool, the tension with rival south african chad le clos, perhaps clearly

written on his face. >> le clos still continues to look over at michael phelps. >> reporter: both men easily qualifying for the 200 meter butterfly, le clos, the defending champ versus phelps, the greatest ever. tonight gold is on the line and history is at stake. with many complaining about traffic jams and security getting into the venues, ticket sales haven't been a problem. and lester, once folks get inside, they're witnessing the greatest athletes on the planet. what a sight. >> some of that sw swimming will take place just behind us here. thank you very much. we're getting a rare look this evening at striking images inside a city under siege. fighting has escalated in syria's largest city between the rebel coalition there and the government forces and now the u.n. is warning of a humanitarian disaster with some 2 million people cut off from running water. we get the latest from nbc's bill neely. >> reporter: in a city of ruins, the most intense fighting in

five years. it's rebels against the regime, neither able to win, neither willing to give up. and caught in the middle in aleppo, more than a million people. like this man. screaming, where is my son? his child buried, dead. the u.n. today called for a cease fire, warning of a catastrophe. the last full day of running water here was a month ago. but the u.n.'s plea may fall on deaf ears because rebels and regimes aim to encircle and destroy each other. they each control half of aleppo. the rebel coalition led by jihadists with other groups backed by the u.s. and the government backed militias. rebels broke a regime seize just days ago, but a russian air strikes are relentless. this teacher sends video updates every day. >> this is a genocide.

>> reporter: it's slaughter without mercy, this man's wife lies dead before him, then he raises his arms for the body of his baby son. babies are born into a world of dust. aleppo's only miracle is that anything is left standing. syria's oldest city, dying like the people in it. bill neely, nbc news. and there's more to tell you about as we continue here tonight. some say she may be the best of all time, we're at home with a superstar american gymnast, simone biles chasing her first gold medal.

back now from rio, where the "final five" as they're being called took center stage today, the usa women's gymnastics team led by one woman what's being called the greatest of all time, simone biles. she was too young to compete in london, so many at home may not know her. but that's about to change big-time. here's nbc's stephanie gosk. >> reporter: no one flies higher, performs harder routines or wins more. simone biles has completely upended the sport of gymnastics. >> they call that untouchable. >> reporter: more than

a few call simone, the michael jordan of her sport, making the 4'9", 19-year-old a little uncomfortable. >> i just don't feel like i'm up to the expectation yet, so i kind of just blow it off. >> reporter: what makes her even more remarkable is her story. simone's mother struggled with drug and alcohol addiction and her father was never really there. by age 3, she was in foster care. >> i got a call from a social worker saying that simone and her sister and brother, they were in a foster home back in ohio. i said, well, send them to me. >> reporter: ron biles, simone's biological grandfather and his wife nelly brought the kids down to houston, eventually adopting them. not long off, simone was jumping off the walls, the furniture and just about everything else. >> she was so tiny and it scared me to death, but it did not scare her at all. >> reporter: there was no other option, at age 6, she started gymnastics. >> the kids at school could never do like cartwheels and

stuff like that, but i could always do them on the playground, so i thought that was pretty cool. >> reporter: younger sister adria is a gymnast too, they are extremely close and typical sisters. family meals are a chorus of giggles. like most teenagers simone's bedroom is her sanctuary, lots of trophies and lots of purple, along with a life-sized poster of actor zac efron. >> i used to come in and kiss him. >> you come in and give him a little kiss? >> yeah, it's a little strange. >> reporter: that playful spirit is a big part of who simone is. watch as she outruns a bee at the 2014 world championships. even facing the pressure of rio, she manages a laugh. the bar is high for rio, thanks to yours. to yourself. is that inspiring or terrifying?

>> i think it's a little bit of both, terrifying because i don't want to let anybody down, but exciting just to know that i have done and accomplished so much. hopefully i can continue to do that. >> reporter: simone biles has four more chances to win gold, she's heavily favored to win all of them, if she does, lester, she breaks a record. back to you. >> certainly one of the most talked about athletes here at these games. stephanie, thank you. we're back in a moment with incredible images showing an ominous sight rolling over a city.

were killed. there is grim news from chicago tonight, a 10-year-old boy playing with his twin sister was among the 19 people shot as that city marked its deadliest day in 13 years on monday. 19 people shot, nine of those were killed. the most homicides in a day there since july 5, 2003 as that city continues to struggle to contain the violence. a rapidly spreading wildfire in southern california has now

exploded in size, burning more more than 7,000 acres. the intense flames in the san bernardino mountains has forced thousands of people to evacuate and shut down a number of area schools. thousands of homes now threatened there. an incredible sight caught on camera, video showing a massive dust storm moving through phoenix. strong winds dropping visibility at the airports to just a fraction of a mile. it was triggered by heavy rainfall miles away in tucson, where flooding water forced a number of swift water rescues. when we come back, the american who overcame all the nay-sayers to become the fastest in the game.

kobori you one of the untold stories here in rio, the usa rugby team which scored a big win today and takes the field again tomorrow. our ron mott talks with an american who has been called the fastest in the sport. >> reporter: at 5'8", carlin isle is used to being too small for this or too small for that. it's a big part of what still motivates him today at age 26. >> if i quit, then they win. >> reporter: growing up, he had good reason to think

he didn't measure up. foster homes, schoolyard fights, not enough to eat, couldn't read. a bleak start for certain. >> i had a picture i wanted to paint for myself and my life and i wasn't going to let anybody dab their paint brush in my painting because then it would become theirs. >> reporter: one day he found his footing, setting records at his ohio high school at the track and dazzling crowds on a football team, and now a runaway sensation in a sport few americans know, rugby sevens. >> how does that happen? >> i started watching it and i thought, i think i could be pretty good at this. >> reporter: not just pretty good, fastest in the world good. in rio, he and an upstart american team hope to go home with a respectful showing, if not a medal and his speed is key. >> this dude is fast, lightning fast. >> reporter: given the speed his attention attra

attracted, he's had to overcome with a reminder's in writing, on his chest, a teenaged tattoo that didn't go over so well with his mom sandra isles who adopted him and his sister when they were 7. >> i was like, what are you doing? and it's a big old necklace that says focus, but that was his words of determination. he's a hard worker and when he wants to do something, he goes for it and he doesn't give up at all. >> reporter: that drive and rare athletic talent left one gym owner in such awe, he helped carlin chase his olympic dream, buying him a car and paying for his private training. >> i really believe in him and thought he could do it. i think i'm a good judge of character. >> reporter: the pitch is his canvass and carlin isles is ready to create a masterpiece. >> it didn't matter how much money you have, no matter how many parents you have, you don't have to be your circumstances. you can change your picture how you want to change it. it's up to you. >> ron mott, nbc news, san diego. that's going to do it for us on this tuesday night

from rio. a reminder nbc's prime time olympic coverage begins at 8:00 p.m., 7:00 p.m. central. it will be a big night for swimming and gymnastics. i'm lester holt. for all of us at nbc news, thank you for watching and good night from rio. guilty. reaction pouring in as a federal jury finds pg&e guilty of obstructing justice that stems from the deadly san bruno explosion. the news at 6:00 starts right now. thanks for joining us on this tuesday evening. >> this trial is watch aid cross the country and tonight the people of san bruno have some closure. pg&e found guilty of obstructing a federal investigation. the jury returned six guilty verdicts against the utility company late this afternoon. we have several reports tonight. let's begin with bay area's mark

matthews. he is live in san francisco. mark, attorneys and jurors left the courthouse without saying a thing. >> reporter: it happened quickly this afternoon. the maximum fine pg&e faces because of the six guilty verdicts is $3 million. that is a far cry from the half a billion the company faced in potential fines last week when prosecutors abruptly decided to drop their pursuit of that money. today's verdict split and there were 12 counts, found guilty of six and acquitted on six. the jury found pg&e guilty of five counts of violating pipeline safety regulations and one count of obstructing a federal investigation of the san bruno gas explosion. remember that 2010 explosion killed eight people and destroyed 38 homes. pg&e was exceeding on their pipes