on our broadcast tonight, plot to attack the u.s. capitol inspired by isis, foiled by the feds in an undercover operation. chilling new images from inside the hostage siege in paris as al qaeda says it was behind the massacre at that magazine that hit newsstands again today. scare in space, american astronauts scramble to safety in the middle of the night. measles outbreak, the biggest in years and traced back to disneyland. tonight, the scramble to track down those who may have been exposed. and a cliffhanger, two men with the summit in their sights. we're there live to want in yosemite. "nightly news" begins now. from nbc news world headquarters in new york, this is "nbc nightly news" with brian

williams. good evening. the feds say they were onto it early, but tonight they've announced they've stopped a plan apparently inspired by isis to attack the u.s. capitol and those inside it. it's an example, they say, of the kind of lone wolf attack that can get its inspiration from people and movements overseas. we begin tonight with late details from our justice correspondent pete williams in our d.c. newsroom. pete, good evening. >> reporter: brian, good evening. u.s. officials say this is precisely what they worry about most, someone in the u.s. becoming inspired by terrorist propaganda to carry out attacks here at home. the fbi says 20-year-old christopher lee cornell of green township, ohio, wanted to set off pipe bombs at the u.s. capitol and shoot people as they fled. investigators say he came to their attention last august when he posted pro-isis messages on twitter using an alias, raheel mahrus ubaydah.

court documents say he discussed his plans with a man he thought was sympathetic but who turned out to be working undercover for the fbi. according to investigators cornell said the former al qaeda figure awlaki and others had expressed the view this kind of jihad was the right thing to do. cornell was arrested earlier today after he bought two assault-type rifles like this and 600 rounds of ammunition. >> spent at least enough time with these particular officers to know that i was in good hands. they knew what they were doing and they exuded a lot of confidence. >> reporter: federal officials insist there was never any danger because the man was under close surveillance for months. they say he never built any pipe bombs and didn't even buy the components for them. brian. >> pete williams starting us off from our washington newsroom. thanks. it's taken a full week, but one of the most likely suspects in the terrorist attack in paris has finally claimed responsibility for it. al qaeda in yemen says it was loody assault on the offices of that satirical

newspaper called "charlie hebdo." but rather than being silenced the paper put out a new edition on the stands today. clearly it's bigger than ever. we have two reports on all of it tonight. we want to begin with nbc's richard engel in istanbul. richard, good evening. >> reporter: good evening, brian. the last year isis has been dominating headlines overshadowing al qaeda. something about dangerous rivalry is emerging, a game of one-upsmanship between the two groups. with the paris attacks, al qaeda is launching a comeback. the attack on "charlie hebdo" last week was al qaeda's most high profile operation in years. and today they bragged about it. in a video al qaeda in yemen claimed it targeted the magazine for insulting the prophet muhammad, even laying out the chain of command behind the attack. ordered by al zwarhi, osama bin laden's successor. planned and financed by radical

american-born cleric anwar al-awlaki before he was killed in 2011 and carried out by cherif and said kouachi. reports suggest the brothers got their automatic weapons from this man, amedy coulibaly who purchased them from a belgium arms dealer who has now turned himself in to police. coulibaly also bought the two machine guns he used to attack the kosher market. new images from security cameras show him inside the market wearing a bulletproof vest. his hostages huddled in fear. some of them order today disable the security cameras. [ gunfire ] >> reporter: coulibaly killed four of the hostages before police stormed the market and killed him. his suspected accomplice, hayat boumeddiene, left paris before the attacks and came here to istanbul before disappearing into syria. the investigation is yielding new suspects daily, but the real focus now is preventing the next attack. richard engel, nbc news, istanbul.

>> reporter: this is bill neely in paris where people waited hours to buy the magazine terrorists tried to kill off. it normally sells 50,000, it sold out fast 3 million copies. many bought it to defy the terrorism. >> i wanted to buy this one to -- >> reporter: 3 million copies sold, another 2 million ordered in numerous languages. the cartoonists say this issue of the magazine depicting on its front page a tearful prophet muhammad is a triumph for free speech. in muslim areas of paris they disagree. they say showing the prophet muhammad is provocative. >> more provocation. >> why you talking about my prophet? why you talking about this god? >> i think it will bring a civil war. >> reporter: you think a civil war is possible? >> civil war is coming, yes. >> reporter: police have now charged this famous muslim comedian who identified with one of the killers with advocating terrorism.

more than 50 more muslims have been arrested for defending terrorism, mostly on social media. the killings carried out by islamic extremists have resulted in more than 50 revenge attacks on muslims, mostly minor. the french president was talking tough today on an aircraft carrier heading to the middle east on air strikes against islamic militants. striking militants at home without alienating his muslim fellow countrymen is now his biggest challenge. today, a week after the massacre this magazine became the biggest one-day sellout in french publishing history. tomorrow, secretary of state kerry arrives here to discuss the aftermath of the massacre and how to stop another one. brian. >> bill neely in paris, richard engel before that. our team remains on this story. gentlemen, thank you both. word out of washington tonight, a major shakeup on the way in the u.s. secret service.

the agency is removing four high-level officials from their posts after a series of dangerous lapses. among the men and women charged with protecting the highest office in the land. we get our report tonight from our white house correspondent kristen welker. >> reporter: it is a major overhaul for an agency in crisis. four assistant directors are being tossed out of their current posts and reassigned. saying in a statement, change is necessary to gain a fresh perspective on how we conduct business. those being replaced come from every corner of the department. dale pupillo with protective operations paul morrissey, jane murphy and mark copanzzi a top official in technology. in an interview with brian last month clancy signalled big changes. >> we have zero tolerance with misconduct. we've got training in place. we've got an integrity board in place. >> reporter: the agency is trying to come back from a series of security lapses, among them agents getting caught with

prostitutes during an official presidential trip to colombia in 2012. a fence-jumper making it all the way inside the white house late last year. >> this may be a really critical moment for members of the rank and file who have been clambering for a change in leadership. >> reporter: brian, each of the four re-assigned employees has more than 30 years of service. no word on their new assignments. all of this comes after an independent report described a culture of low morale and poor leadership at the secret service. brian. >> kristen welker on the white house north lawn tonight. kristen, thanks. now a tense day in space for the astronauts onboard the international space station and for mission control here on the ground at nasa. the crew, two americans, one italian, three russians, were forced to take refuge and safety in the russian side of the space station as onboard alarms warned of a possible toxic leak onboard in the section normally occupied by the american astronauts. we get details tonight from nbc's tom costello.

>> reporter: floating 250 miles above the earth, space station astronauts spent much of the day wearing emergency oxygen masks testing the air after early morning alarm bells warned of a possible ammonia leak in the cooling system on the american side. the order from mission control, don the masks, get to the russian side and close the hatch. >> bottom line is we get all the experts coming in now, everybody's poring over the data, we have the smart folks taking a look at it. >> reporter: an ammonia, toxic leak, rapid decompression, fire or smoke event are among the most serious emergencies on the space station. any one could force the crew to abandon the station in a russian capsule. >> these kinds of emergencies start with protecting the crew then trying to deal with the issue. and then if in the end we can't deal with the issue, some of them can result in evacuating the station. >> reporter: the six crew members were supposed to spend the day unloading a resupply spaceship launched by spacex. but as they hunkered down in the russian section, mission control

became more convinced it may have been a false alarm caused by a bad computer card. >> there is no data at the moment suggesting that there was in fact a real ammonia leak. >> reporter: veteran astronaut scott kelly is preparing to spend a year on the station with russian cosmonauts. >> especially with the crew members, the cosmonauts, we're great friends. we have to work together. we have to rely on each other literally for our own lives. >> reporter: after running air quality tests all day, mission control gave the all-clear to the astronauts just after 3:00 p.m. tonight it is all resumed normal operations. >> tom costello in the safety of washington, d.c. tonight. tom, thanks. over the better part of these last three weeks we have witnessed the test of human skill and endurance really unlike any other on a mountain unlike any other. and tonight we have witnessed the culmination of all of it. two men have completed what's

been roundly described as the most difficult free climb in the world. nbc's miguel almaguer is right there at the very top of el capitan in yosemite forest tonight. miguel good evening. >> reporter: brian, good evening. this is the moment that has been so many years in the making. we were here live when kevin -- when tommy caldwell and kevin jorgeson came up the mountain, were greeted after climbing 3,000 feet up el capitan. they gave their wives hugs, they popped champagne. they are still hugging family at this moment. my colleague hallie jackson has been following their journey for the last several weeks. >> reporter: it's a moment seven years in the making, but 19 days ago no one knew if it would happen. after tommy caldwell and kevin jorgeson started the hardest free climb in the world. their shredded fingertips grabbing granite flakes as thin as dimes. inching up a section at a time,

one slip means starting over. ropes there only to catch them, not to help them. between climbs life suspended on a dawn wall each night sleeping thousands of feet above the valley floor. >> think about everything you done in the last two and a half weeks, every time you went to the store, every time you had dinner, they were on that cliff. >> reporter: as momentum builds the meadow below fills with onlookers eager to learn more about the two friends, jorgeson's childhood climbing competitions, caldwell's escape after being kidnapped and a freak accident that left him with nine fingers in a sport where sometimes even ten aren't enough. >> all of these hardships he's been through all have led up to this moment for him to be able to look at the dawn wail say this looks impossible but i'm going to try it anyway. >> reporter: from a distance the climbers' families feel each triumph and tension.

>> oh, your heart just drops. you know how bad he wants to do it. talk about tenacious. >> reporter: jorgeson slipped again and again until finally he didn't. >> i couldn't be happier. >> reporter: that's when they seem unstoppable. >> this is a view that i'll always remember. >> reporter: two friends climbing into history proving the impossible may not be. the folks up top could probably hear the cheers of joy from the meadow down below 3,000 feet beneath them. and while there is a sense of elation, it's also bittersweet. as tommy caldwell's mother told me, this is a realization of a dream but also the end of one. >> hallie jackson at the base, before that miguel almaguer at the summit, miguel might have gotten the better part of this deal. still ahead tonight, we'll go back to miguel almaguer at the summit and show you how we managed to beat the climbers to the top in just one day. here's a broad hint, there is a back way.

but it's still a pretty tough climb. first, up next, a major outbreak of measles traced back to disneyland and spreading as families return home. a scramble to find everyone who may have been exposed. ...and the wolf was huffing and puffing... kind of like you sometimes, grandpa. well, when you have copd it can be hard to breathe. it can be hard to get air out, which can make it hard to get air in. so i talked to my doctor. she said.. doctor: symbicort could help you breathe better, starting within 5 minutes. symbicort doesn't replace a rescue inhaler for sudden symptoms. symbicort helps provide significant improvement of your lung function. symbicort is for copd, including chronic bronchitis and emphysema. it should not be taken more than twice a day. symbicort contains formoterol. medicines like formoterol increase the risk of death from asthma problems. symbicort may increase your risk of lung infections osteoporosis, and some eye problems. you should tell your doctor if you have a heart condition or high blood pressure before taking it. grandfather: symbicort could mean a day with better breathing.

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triple the number of cases over the year before. and it appears a new outbreak may have started as a destination known better to millions as the happiest place on earth. we get our report tonight from our chief medical editor dr. nancy snyderman. >> reporter: take a person infected with measles, combined with thousands of disneyland tourists and you have the recipe for the worst measles outbreak in california in 15 years. doctors are scrambling to get ahead of this. >> worst situation because lots of people, lots of children. >> reporter: it's a serious yet preventable disease that has now spread beyond california with reports of 26 ill people in utah, colorado and washington state. >> it can lead to blindness. it can lead to encephalitis. which is an infection of the brain. >> reporter: in its early stages measles may be mistaken for a bad cold. symptoms include fever, dry could have runny nose red,

watery eyes and a signature rash. people can spread measles up to four days even before the rash appears. a significant number of people in this outbreak were not vaccinated, either opting out or too young to get a shot. in long beach, california, one infected patient went to multiple stores. this gym posted a sign about the measles outbreak prompting questions from customers. >> do we need to get in and get another booster? do we need to worry about it because we've already had the measles. so we called our doctor first. >> a child gets the first dose of vaccine at 12 to 16 months of age and the second one at 4 to 6 years and right now even adults are considered candidates for getting a booster. this, brian, i think is going to take days if not weeks to figure out the entire area. >> this has received our attention. nancy, thanks as always. we're back in a moment with a high-speed chase on the water that got way too close for comfort. all of it caught on camera. for comfort. all of it caught on camera. (woman) the constipation and belly

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look at the size of this storm. that's the u.s. on the left. this is a single weather front. it stretches all the way from the lower 48 all the way across the atlantic to europe and beyond. upper level winds have been incredibly strong across the ocean this winter. recent passenger flights to london reported being carried along at speeds that fell just shy of the sound barrier. passengers got to london from new york an hour early. one british airways pilot said it was like surfing on the jet stream all the way across the atlantic. scientists have confirmed most of us have something they call cold empathy. it means we feel colder when we're looking at someone who is shivering and obviously cold. and it's a powerful sensation. volunteers who watched video of strangers putting their hands into cold water actually witnessed their own body temperatures drop as a result.

the researchers add that while we feel the cold of others, it doesn't work the other way around for warmth. box office revenues were down over 20% this past summer from last summer with the national average ticket price now at $8, over half of movie goers told pollsters recently they're increasingly staying away because going to the movies has simply become too expensive. finally, the driver of a speedboat in a national park in zambia had reason to believe there was something in their wake in the water just behind their boat. sure enough it was a hippo the size of a volkswagen bus. the most dangerous mammal in all of africa just feet from the stern, so they sped up and got out of there. when we come back we'll return live to miguel almaguer 3,000 feet up at the summit of el capitan. celebration just underway at yosemite. capitan. celebration just underway at yosemite. ld truth. i have a cold,

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our team made it up to the top in a single day. they made the journey the way a lot of hikers and tourists do, which is they went the back way. which is not without its challenges we should hasten to add. we get our report tonight from nbc's miguel ato the summit began at 5:00 a.m. along a treacherous trail through the back country. eight miles and ten hours to the top of el capitan. it's pretty rocky, pretty steep. you can see the terrain we're dealing with here. it's also quite breathtaking. there's the falls right there. you can see it iced over. shot at the valley. and our crew behind us who's working their way up this hill. the yosemite's trail is popular for thousands of hikers each year, the view of the waterfall north america's highest at roughly 2,400 feet, is spectacular. we're accompanied by a guide, but once here most hikers turn back.

it looks intimidating. that's the top of the wall we're trying to reach 3,000 feet up. we've come a long way from this valley floor. it's cold up here, but that's good for hiking weather. we've reached a mile marker here. we've got about four and a half miles to go. still a lot of distance to cover. a good stretch of the trail is actually covered in snow. that's where we've reached slowed us down quite a bit. it's really slippery. it's like ice literally. there are a hundred trails up to el capitan. it was first summitted in 1958. for those who make it to the top the reward is pure beauty, the view of a lifetime. for those who reach the summit, whether it was up that shear granite wall or around the back trails like us, there's pure joy and celebration going on right now atop here. and there is word tonight that the president may call these two climbers. brian. >> well-done up there, miguel almaguer at the summit of el capitan in yosemite. from new york that's going to be our broadcast on this

wednesday night. thank you for being here with us. i'm brian williams. we of course hope to see you right back here tomorrow evening. good night. you right back here tomorrow evening. good night.

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