90s coming up at 6:00 p.m. as this week gets warmer. >> thank you, jeff. thanks for joining us at 5:00. lester holt is next. tonight, bomb plot. the son of a police captain behind bars accused of betraying his family and his country with an isis-inspired plot to massacre college students live on the internet. drug lord manhunt. the desperate search for one of the world's most dangerous men, who's responsible for flooding the u.s. with drugs. we'll trace the tunnel he used for his elaborate escape. in harm's way. nearly 30 million americans in the path of dangerous storms. already heavy rains and flooding forcing people onto their roofs for rescue. and plot twist. a long-hidden sequel changes everything we thought we knew about a beloved character. "nightly news" begins right now. >> announcer: from nbc news world

headquarters in new york, this is "nbc nightly news with lester holt." good evening. we begin here with another one of those stories that reminds us isis is determined to inspire a terror attack on our soil. this one comes from massachusetts. a young man busted by the feds. they say he was inspired by isis and was hatching a plot to explode bombs in college cafeterias. in this case the suspect was already on authorities' radar. it turns out his father, a police captain, sounded the alarm and turned him in. our ron mott has details. >> reporter: federal officials in boston announced the arrest of 23-year-old alexander ciccolo, the son of boston police captain robert ciccolo. a police source told nbc news captain ciccolo reported his son to the fbi after learning he was allegedly plotting an isis-inspired attack. according to court documents, ciccolo goes by the name ali al amriki and was arrested july 4th after receiving four guns from an

undercover agent and buying a pressure cooker. the government says ciccolo was under investigation since last fall and shared plans to attack college cafeterias including executions of students broadcast live on the internet. but law enforcement officials say because he was under constant surveillance an attack was unlikely. >> authorities dodged a bullet in this plot but the threat remains out there, remains wide, remains strong, and isis remains relentless in recruiting westerners for its cause. >> according to the fbi affidavit, agents found partially built molotov cocktails in ciccolo's apartment. a boston police source tells nbc news that ciccolo and his father are estranged and that ciccolo suffers from mental illness. while being evaluated at the jail after his arrest officials say ciccolo stabbed a nurse in the head with a pen. this is the second high-profile isis-related investigation to surface in massachusetts in the past six weeks. in early june police shot and killed 26-year-old usaamah rahim outside a boston-area drugstore when they say he waved

a knife at officers. today ciccolo's family issued a statement saying they were saddened and disappointed to learn of his intentions, grateful authorities prevented any loss of life. ciccolo is due in court tomorrow. ron mott, nbc news, boston. we're going on 48 hours now, and no luck in the hunt for a notorious drug kingpin whose brazen and elaborate escape from a mexican prison has rattled law enforcement on both sides of the border. joaquin "el chapo" guzman, head of a powerful mexican drug cartel, has funneled billions of dollars of drugs into the u.s. tonight a frantic search continues for him as we get a better sense of the complexity of the tunnel through which he made his escape. nbc's mark potter is outside the prison in mexico. mark, good evening. >> reporter: good evening, lester. the last time authorities here at the prison say they saw joaquin guzman was around 9:00 p.m. on saturday. since then he's disappeared through a tunnel. and now that manhunt is widening.

once again the exploits of joaquin guzman are frustrating the mexican police and military. his nickname, el chapo, means shorty. but his legend is larger than life. for most of the day authorities were gathered at this nondescript rural house, the beginning of the mile-long tunnel authorities say he used to exit the prison. from this vantage point it's easy to appreciate just how long that tunnel is. this house is where the tunnel began. they dug down from here and then went out across that green field, way out there, past that tall tree on the right, and kept going to that complex of buildings, that gray wall out there. that's the prison. and that is how far they had to go underground to reach chapo guzman's cell. by leaving through such an elaborate tunnel some suggest that guzman didn't escape from prison, he checked out. and many suspect corruption was behind it. >> this is someone who can hire the best

talent in the world. but he himself probably can't read and write. >> reporter: guzman once appeared on the "forbes" magazine billionaires list. he is also believed to be powerful and violent. as the head of the notorious sinaloa drug cartel. >> his strategic wars that he's fought against the juarez cartel, the tijuana cartel and the zetas themselves and the gulf cartel have been the bloodiest battles that mexico has seen. >> reporter: to some, especially the poor, he is seen as a benefactor, celebrated in folk songs. >> he's one of the all-time narco figures who would shower people with gifts, kind of a santa claus, robin hood role. >> reporter: today pictures surfaced on social media purporting to show guzman after his escape. they were reportedly supplied by his son. but one official told nbc he doubts chapo's son would release any clues to his father's whereabouts. mark potter, nbc news, mexico city. this is pete williams. it's oddly fitting that mexican police

say joaquin guzman used a tunnel to escape because it's through tunnels that he began pouring illegal drugs from mexico into the u.s. two decades ago. the first big one in arizona in the early 1990s. and then an even more sophisticated drug tunnel was found leading into california. u.s. officials say at its height the drug cartel he ran was responsible for up to half of all the illegal drugs flowing into the u.s. through mexico. marijuana, methamphetamines, and heroin and especially cocaine from central and south america. and raking in at least $3 billion a year. >> this is a national travesty, and he needs to be caught. and the next time he's caught we need to send him to the states and make sure he's here for good. >> reporter: in january authorities said his cartel played a major role in importing more than two tons of cocaine a month into chicago. half sold there, the other half in the midwest, northeast, and parts of canada. guzman has been indicted by grand juries in six states. and the u.s.

aggressively urged the mexican government to send him here to face charges in an american courtroom. >> we've made quite clear to the mexicans our interest in ensuring that he faces justice here in the united states. >> reporter: other mexican drug figures sent here for trial have been convicted and sentenced to colorado's supermax prison, which is where current and former drug agents say joaquin guzman should be locked up. the d.e.a. says it's guzman's cartel that has worked hard to satisfy the demand for heroin now considered epidemic in the u.s. and his cousin will be sentenced later this year in new hampshire after admitting that he planned to expand guzman's drug empire into new england. lester. >> pete williams tonight. thank you. turning overseas now, where there are signs that a nuclear deal with iran is imminent. after 20 months of heated negotiations and no fewer than four different deadlines and three extensions. nbc's chief foreign affairs correspondent andrea mitchell has the very latest tonight from vienna. andrea, good evening.

what's happening there? >> reporter: good evening, lester. the ministers have now gotten together after midnight and are meeting. all signs now pointing to a deal within the next few hours. if the draft agreement is approved by president obama, by iran's president rouhani, and the leaders of the other world powers. as the foreign ministers arrived this morning, they weren't done. there were still some disputes to settle even as they hoped to make history. the grim faces around the table expressed the tension of the last 17 days. they had been here before, getting close and failing to close the deal. would it finally come together? the expressive shrug of europe's representative federica mogherini said it all. by midday iran's foreign minister javad zarif on his balcony expressed his mood best. iran's president rouhani's office anticipating an announcement tweeted "hashtag iran deal is a victory of diplomacy

and mutual respect over the outdated paradigm of exclusion and coercion and this is a good beginning." but they had jumped the gun. so they deleted the tweet, then reposted, adding an if to #irandeal. and the white house confirmed if necessary they would extend the midnight deadline a fourth time. >> typically some of the more -- some of the most difficult issues are the ones that get kicked to the end. >> reporter: the final hang-up was real. whether to lift a u.n. arms embargo on iran and if so when. despite u.s. concerns that it would further inflame the region. >> the iranians are arming the houthi rebels in yemen. they're arming the assad government in syria. they're arming hezbollah in lebanon. and they're arming hamas in gaza. they are a real problem. >> reporter: any change in that arms embargo is going to set off a fire storm in congress, in both parties in fact, which is why even a deal agreed to tonight will require a major selling job back home for john kerry and importantly for the president. lester? >> andrea mitchell, thank you.

greece may be saved by a deal that could stop the crisis that has made atms run dry in that country. other european leaders have agreed to give greece a third bailout in exchange for some strict concessions, which is not sitting well with many of the greek people. it's not a done deal yet. greek parliament still has to vote on it come wednesday. we're on alert this evening for the threat of tornadoes in the midwest. about 27 million people potentially in the pathway of severe weather from a system that has already pounded the region with heavy rain and flooding. nbc's al roker has the latest. >> reporter: a morning of destruction in parts of the midwest. rain and powerful winds whipping through illinois, uprooting trees, downing power lines. the same line of severe storms causing flooding and bringing down trees in wisconsin. >> we just had the tree trimmed, ripped the sidewalk right out. >> reporter: in one central indiana neighborhood people spending the day assessing damage after an overnight tornado whips through with 85-mile-per-hour winds. and there was more severe weather in

indiana today. >> like a big wind tunnel. i mean, you could just -- everything was blowing around. >> reporter: in kentucky several drivers had to be rescued yesterday from flooded roads. and a frightening scene in west virginia. residents there preparing for even more rain after flash flooding prompted dozens of evacuations. vehicles were swept away. more than 40 people in the town of mineral wells had to be rescued from rooftops. >> there's a lot of houses that were up to the windows or farther. >> reporter: boats, trucks, and humvees deployed to bring people and their pets to safety. and we've got heavy thunderstorms now moving through west virginia at this hour. the northern half of illinois under a tornado watch until 11:00 central daylight time. we're also looking tonight for an area of enhanced severe storms. moderate risk stretching from illinois all the way into parts of kentucky. 52 million people at risk. tornadoes possible. strong winds, damaging winds. and that risk continues tomorrow from jackson, nashville all the way

to the southeastern atlantic coast, lester. >> all right, al, thanks very much. now, it's official. wisconsin governor scott walker has jumped into the republican race for president. he's the 15th gop candidate to announce but he's the one many have been waiting for. now comes the real test. the ones that will determine if he earns his place in the top tier. nbc's kelly o'donnell has more on that. >> reporter: scott walker's supporters have plenty of practice turning out for him. >> every day's an outstanding day when you're a republican. >> reporter: three election victories in four years. even beating back a 2012 recall. >> i love america. [ cheers ] >> reporter: now the 47-year-old with childhood roots in iowa says he is ready to be president. >> we need new fresh leadership. leadership with big bold ideas from outside of washington. the kind of leadership that knows how to get things done. >> reporter: walker is a political animal. more than half his life spent in public office.

protesters camped at the state house. after walker stripped collective bargaining rights from public union workers in 2011. this year walker stumbled when he compared that fight to global terror threats. >> i can take on 100,000 protesters, i can do the same across the world. >> reporter: in a record-sized field with donald trump's combustible rhetoric on immigration -- >> was viciously and violently shot by an illegal immigrant. >> reporter: -- walker has flipped, rejecting a path to citizenship that he once supported. >> it's very clear to me. we need to secure the border. >> reporter: this harley-riding son of a baptist minister can appeal to tea party and social conservatives along with the gop establishment. campaign adviser rick wiley. >> he's one of the only candidates that can swim in all three of those lanes. >> reporter: and this is the walker kickoff. and despite his potentially broad appeal across different parts of the republican party as governor walker has no foreign policy experience and he has yet to be tested under

the kind of scrutiny you get on the presidential level of politics. those will be his challenges as he begins a week-long rollout in four key states. lester? >> kelly o'donnell there tonight. thank you. there's late word of a major shift for our nation's armed forces. the pentagon announcing plans to end the ban on transgender troops in the military. the various branches will have six months to figure out the logistics of integrating transgendered service members beginning early next year. there's a lot more to tell you about here on this monday. still ahead, rivers of lava, ash, and cinders raining down from the sky. a giant volcanic eruption forcing evacuations for miles around and the worst may be to come. also, will fans be disappointed now that another book fundamentally alters one of the best dads in american literature?

we're back with what officials say may be the most dangerous eruption in decades in mexico. a volcano has been blasting lava and ash into the air since late last week blotting out the sky, and now there are warnings that it could explode even further out of control. nbc's miguel almaguer has our report from the southern mexico state of colima. >> reporter: from miles away soot, ash, and smoke is seen pouring from the mouth of mexico's colima volcano. the explosions rattled the earth. here they call it the volcano of fire. when falling debris suddenly turns day to

night. erupting thursday, time lapse video shows the spectacular display of pulsating heat and lava, ash shooting up a mile and a half into the air. miguel novato evacuated his ranch as he felt danger moving in. "it's like a fireball rolling down the hill. the volcano was throwing fire through the air. i couldn't believe it." tonight still smoldering for a fifth day the fire volcano is the most active and dangerous in mexico. no one killed here, but the ash is becoming a health hazard. the mountains and hillsides surrounding the volcano used to be a lush green, especially during the summertime. now it looks like a moonscape. the ash here several inches thick. and it's smoldering hot just beneath my feet. coating cars, homes, and lives, the blanket of ash has forced 700 to flee, including adelina vizcaino. "it's burning my eyes,

my head, ear and nose hurt. i can't handle it." the young and the old are now sheltered in schools like this one. geologists say the activity here shows no sign of slowing down. tonight the volcano of fire lives up to its name. miguel almaguer, nbc news, colima, mexico. when we come back, the amazing moment that put such a big smile on a baby's face, and i bet it will put a smile on yours as well. we'll be back.

a journey more than nine years in the making is now just hours from its destination. nasa's new horizons probe is expected to make it past a survey and photograph pluto tomorrow evening eastern time. the spacecraft has traveled more than 3 billion miles to get there. today nasa said it's already sending back photos that show pluto is bigger than they originally thought.

in the future some people may have a royal to thank for saving their lives. prince william has begun a new job as an air ambulance pilot. he'll fly emergency patients to get vital medical help, and he plans to donate his salary to charity. and this is the viral video has been making so many people smile. just like the adorable baby it shows getting a glimpse of her mom and dad for the very first time. an exam showed that baby piper was very farsighted. so the family had some custom-made glasses made for her. and after a bit of a struggle to get them on, piper is nothing but smiles. how do you like that? when we come back, atticus finch, we hardly knew you. the uproar over the new book linked to a classic american novel.

next at 6: when a couple gets divorced, who owns the frozen embryos? ===take vo=== how a bay area custody dispute could set a national precedent. ===take vo jess=== plus, a stunning reversal in an east bay kidnapping that police called hoa ===next close=== next. finally tonight, the fondest wish of many a book lover is about to come true at midnight with the release of a second book from harper lee, author of the 1960 classic "to kill a mockingbird." but fans might be in for quite a shock when they see what's become of a beloved character. here's harry smith. >> reporter: with a somber security guard on hand, it's clear there will be no early

release of harper lee's new book "go set a watchman." instead, a reading of lee's classic "to kill a mockingbird." but the early reports have lee lovers concerned. >> it's kind of like you lied to us. >> i think it will change how i think about atticus finch. >> reporter: harper lee's new novel, set in the same town with the same characters, was actually written three years before "to kill a mockingbird." and in the new book atticus finch, the courageous defender of equality-s portrayed as a bigot. harper lee documentarian mary murphy is one of the few who has read it. people are reading about the new book, and they're saying, well, if he's a bigot in this new book, i'm not going to read it. >> oh, but scout is the hero of this book. as scout would say, you have another thing coming if you think that's all there is to this novel.

>> reporter: harper lee is 89 and said in the statement the new book is the parent of "to kill a mockingbird," a book that for many reads like scripture. thousands of people come to monroeville, alabama every year to get as close to the story as possible. the old courthouse is still standing. and harper lee lives not far away in a nursing home. at monroeville's old curiosities and book shop -- >> so you needed one copy? >> one copy. >> reporter: -- there's been a steady stream of people placing orders and calls come in from all over the country. bookstore owner ann moat says she's not surprised. >> it's impacted so many people, and they want to tell why it impacted their life and what it has meant to them. >> reporter: that a novel could move so many of us is the enduring legacy of harper lee. and if the new atticus doesn't live up to the old one, we can choose which one we prefer. harry smith, nbc news, monroeville, alabama. that'll do it for us on this monday night. i'm lester holt. for all of us at nbc news, thank you for

watching and good night. a bizarre twist in the kidnapping case of a vallejo woman. right now at 6:00 the fbi says no hoax. a bizarre twist in the kidnapping case of a vallejo woman. what we're learning about the suspect and his link to another local crime. thank you for being with us. i'm raj mathai. >> i'm jessica aguirre. the case grabbed national headlines. police quickly dubbed the case a hoax and a wild good chase. the man seen here in this cap and gown from harvard, matt muller, a former marine is now

accused of really taking huskins and there's more. we have developing coverage on the developing story. the home invasion led to a break in the vallejo case but we begin with jodi hernandez. >> reporter: the attorney for both victims came out swinging. they were loud and vocal when the story broke four months ago insisting that their clients were innocent. now that the fbi has arrested a suspect, those attorneys are saying we told you so. >> today is a fabulous day for denise huskins, for aaron quinn, who have held their heads up high in the face of public shame and humiliation. >> reporter: that's how attorneys for victims of an