on this sunday night -- breaking news. multiple shootings at a jewish community center on the eve of passover. escalating crisis. an emergency u.n. security council meeting is called as ukraine's government threatens a full-scale military operation against pro-russian militants. severe threat. powerful ss batter the midwest and now have triggered tornado watches in the south. out of control. deadly wildfires rage in chile, forcing 10,000 people to evacuate their homes. and the pope celebrates palm sunday mass and poses for selfies with the crowd. >> announcer: this is "nbc nightly news" with lester holt. substituting tonight, carl quintanilla. good evening. two stories we're following for

you tonight. a showdown between ukraine's government forces and pro-russian separatists has triggered the u.n. security council to call an emergency meeting tonight. we'll get to that in a moment. but first, multiple shootings at a jewish community center on the eve of passover have left at least three people dead in overland park, kansas. police say the suspect is a white male in his 70s. our report from andres gutierrez of our affiliate kshb. andres, good evening. >> reporter: good evening, carl. police tell me three people are dead and a 14-year-old boy is in critical condition tonight following this afternoon's shooting. law enforcement say that multiple shots were fired around 1:00 p.m. local time at the jewish community center here in overland park. it's a city 20 minutes south of kansas city, missouri. shots were also fired at village shalom, a retirement home eight blocks away. a man who police say is a person of interest was arrested shortly after the shooting in the parking lot of an elementary school. i was there when they took him into custody. as he was sitting in the back of the police car, that man yelled an anti-semitic remark to our camera.

>> is this something of a hate crime? >> it's too early in the investigation to try to label it. we know it's a vicious act of violence and obviously at two jewish facilities. one might make that assumption. >> reporter: all programs scheduled here at the jewish community center have been canceled for the rest of the day. two places of worship will be holding a vigil for the victims tonight. carl? >> andres gutierrez of kshb. andres, thanks. the jewish community center of greater kansas city released a statement saying, "our hearts go out to the families who have suffered loss on this tragic day" and thanked those who expressed sympathy, concern and support. now to crisis in ukraine. the u.n. security council will meet tonight in an emergency session at russia's request as the ukrainian government threatens a full-scale operation against the pro-russian separatists. some now fear they're on the brink of an all-out war. we have two reports tonight,

beginning with nbc's ayman mohyeldin in eastern ukraine. ayman, good evening. >> reporter: good evening, carl. the crisis in ukraine may be entering a new chapter, this after the government in kiev says it is now launching a large-scale operation to regain territory it has lost over the past week. but moscow says this order is illegal. in fact, the former ukrainian president says it's the cia who's behind the unrest. but nonetheless, with thousands of troops amassed on the ukrainian-russia border, the situation in ukraine is very volatile and could be entering a new dangerous part of its war. with military grade weapons and precision, this was the moment pro-russian separatists took control of this police station. it's a scene that has repeated itself over the past several days across eastern ukraine and one that has pushed the country to the brink of widespread violence, if not all-out war. heavily armed men in military uniforms, widely believed to be backed by moscow, taking

buildings and positions in areas they want to break away from ukraine. separatist groups now control some of the roads in and out of towns. ukraine's police have struggled to confront the militias. both sides say they have lost men to the violence that is increasing. but now the ukrainian government says its patience has run out. the country's president has ordered the military to launch a large scale operation to oust the pro-russian separatist militias. he also gave gunmen a deadline to lay down their weapons and leave government buildings like this one in slaviansk. for the past several hours, they have been reinforcing the barricades on both ends of the street, and they have been reinforcing their positions after taking over the police headquarters here. a lot of the men we are seeing are openly brandishing their weapons in public, and it's definitely a sign that they are now in control of this area. at rallies in the eastern part of the country, ukrainians are fighting each other. this amateur video shows two men attacked by pro-separatist

protesters. with the ukrainian government's deadline now rapidly approaching and separatist militias digging in, ukraine's violent turmoil may be far from over. ayman mohyeldin, nbc news, donetsk, ukraine. >> i'm kristen welker at the white house. tonight the obama administration is accusing russia of escalating the crisis in eastern ukraine. >> certainly it bears the telltale signs of moscow's involvement. >> reporter: u.s. ambassador to the u.n. samantha power warning russia if it continues to increase tensions, there will be more consequences. >> the president has made clear that, depending on russia behavior, sanctions against energy, banking, mining could be on the table. and there is a lot in between. >> reporter: this after russia tried to point the finger at ukraine for the violence. today the russian foreign minister told the u.s. it should get its allies in the region under control, writing in a statement, it now depends on the west to avoid the possibility of civil war in ukraine.

but today there was bipartisan agreement that russian president vladimir putin is the instigator, and republican senator john mccain urged the obama administration to go further to help ukraine. >> we ought to at least, for god's sake, give them some weapons, light weapons, with which to defend themselves. >> reporter: that's under consideration as tensions have mounted since russia annexed the crimea region of ukraine last month. the u.s. imposed sanctions against more than a dozen oligarchs, causing russian stocks to plummet. but putin seems undeterred. experts warn a regional war is on the horizon if the situation isn't defused soon. >> when the russians invade, as they have done covertly already, they will be met and are about to be met by the ukrainian military. it is going to be very bloody. >> reporter: the white house will dispatch vice president biden to ukraine next week to reinforce the united states' support of the new government there. carl? >> nbc's kristen welker, ayman mohyeldin in ukraine covering

the ukraine story for us tonight. thanks. new details are emerging tonight in the investigation into that fiery bus crash in northern california. nbc's janet shamlian has more from willows, california. janet, good evening. >> reporter: hi, carl. what's left of the bus and the truck have been moved here. investigators aren't close to being done with them, but they have learned more about this horrific accident. an important clue from the charred shell of the bus, investigators have found the black box-type device. but the more critical one from the fed ex truck was incinerated in the fire. >> we can look at aspects of steering and other pieces that did survive to possibly get a sense of the speed range and the revolutions of the wheels, to maybe even know the direction they were in. >> reporter: the ntsb says there were no skid marks from the fedex truck, indicating the driver never hit the brakes. did he fall asleep or suffer a health problem? investigators are looking at everything, including cell phone

records and his schedule the 72 hours before the crash. blood samples were taken from both drivers, sent for alcohol and drug testing. >> i could hear screams of people who were trapped inside burning alive. they were screaming "help me, i don't want to die." >> reporter: vivid memories for miles hill, who is covered in burns. the 18-year-old was sitting right behind the bus driver and saw the truck coming directly at them. there have been some reports that the other truck, the fedex truck, was actually in flames as it crossed the median. did you see anything? >> it was not in flames. it was in perfect condition. it exploded upon impact on the bus. >> reporter: the ntsb tonight concurs, saying there's no physical evidence yet. >> what that means in the overall investigation we're not ruling anything out. >> reporter: a small memorial along the interstate is the only physical sign here of the tragedy. the scars now are mostly out of view. families of those who died planning memorials and survivors just trying to hold on. a handful of high schools will

be without one of their classmates in the morning. they are in the los angeles area, and those schools are providing counselors to the friends left behind. carl? >> janet shamlian in willows, california tonight. janet, thanks. severe weather alerts are up across much of the nation's midsection tonight, including tornado watches. high winds, damaging hail and heavy rain already left a destructive path in michigan. the latest from nbc's joe fryer. >> reporter: strong storms ripped up the landscape across michigan. and where hail ricocheted off buildings and cars -- >> the wind just really picked up really, really fast. >> reporter: -- and powerful winds flipped small planes, with gusts reaching 80 miles an hour. >> before i knew it, in about 60 seconds, man, it came through and blew my fence down, messed my garage door up. >> reporter: the roof of this high school gym was ripped clean off, and this pile of dissected tree limbs crushed a house and car with the family inside narrowly escaping. power lines took a hard hit in michigan.

more than 150,000 customers lost electricity. severe spring storms stretched across the country's midsection, hitting wisconsin and illinois. >> i have never seen the ground get covered in hail before. >> reporter: now the threat moves into the south. >> stay weather aware and take this seriously. >> reporter: forecasters warn it's not over yet. >> we need to be on the lookout for tornadoes, large hail, and damaging winds heading into monday. it keeps going. some severe thunderstorms maybe from around cincinnati, ohio, down into houston and over into alabama. >> reporter: as the system moves east on monday, forecasters say the tornado risk should drop but not the threat of damaging storms. joe fryer, nbc news, houston. now to the still unfolding disaster in chile where raging wildfires have killed at least 11 people, destroyed hundreds of homes, and forced more than 10,000 people to evacuate. all this in the pacific coast city of valparaiso. nbc's ron allen has our report.

>> reporter: the deadly inferno erupted in the forested hillsides of valparaiso, one of chile's most important seaports. thick black smoke shrouding the picturesque city visible miles away. when the fire was just a few blocks away, she says, we ran with just our clothes and pets. some 10,000 people evacuated their homes. at least 500 houses destroyed as the flames tore through several densely populated neighborods. the blaze broke out saturday afternoon, burned through the night and for much of today. >> this fire was just unbelievable. >> reporter: journalist graciela ibanez is there. >> you could see the flames from far, far away. we were all scared that this would -- like we would wake up in the morning and see there was no city. i mean, people lost everything. >> reporter: the country's president declared a state of emergency. thousands of troops moved in to maintain order. it's a tremendous tragedy, she says, possibly the worst fire in

the history of valparaiso. more than a thousand firefighters from the surrounding area battled to contain the blaze. late today, hot spots continued to burn. shelters overflowed. hospitals are treating hundreds of victims, with officials warning the toll of 16 lost lives could rise. ron allen, nbc news. a new u.n. report out today warns the world must act now to address climate change to avert disaster. details from our chief environmental affairs correspondent anne thompson. >> reporter: the report says time is running out to avoid the worst impacts of climate change. melting ice sheets that will raise sea levels and swamp coastlines. stronger heatwaves and droughts that could put the world's food supply at risk, particularly the basic crops of wheat and corn. the u.n. panel says the world must act now. >> if we wait for more than about 10 or 15 years, we really will make it extremely difficult for us to keep climate from changing substantially and

really exposing ourselves to some substantial harms. >> reporter: to protect itself, the report says the world must reduce greenhouse gas emissions 40% to 70% by the year 2050 and be near zero by 2100. those are the emissions we create burning oil, coal, and gas for power and transportation. in its place, the report calls for a low carbon energy supply, tripling renewable power, solar, wind, and geothermal, more nuclear power. coal only if carbon is captured and stored or, instead of coal, cleaner burning natural gas, a bridge to a greener future. >> it's like an insurance policy because we don't have the answers to everything other than that we know there's a tremendous risk. >> reporter: but it may not be enough. the report warns by the second half of this century we may need technologies to pull carbon dioxide out of the atmosphere. this video illustrates one company's idea. >> we're trapping over 100 kilos of co2 here every day. >> reporter: currently, only

forests remove carbon dioxide from the air on a large scale. the report acknowledges all of this has a price but not one that would sink the world's economy. >> that's absolutely the case. in all the scenarios that are explored in this report, we still find robust economic growth. >> reporter: the cost and difficulty will only increase, says the u.n., the longer the world waits to act. anne thompson, nbc news, detroit. when "nightly news" continues this sunday, if you haven't yet filed your taxes and plan to do it wirelessly, think again. and later, after 3,300 miles, a run to support boston marathon bombing victims crosses the finish line.

as an estimated 35 million americans race to meet tuesday's

tax filing deadline, some good news. the irs says your chance of getting audited this year are the lowest since 2005. that's because of budget cuts and new responsibilities that irs agents have. meantime, a warning about filing your taxes on your favorite wireless device. here is cnbc's jon fortt. >> show dad what you're doing. >> reporter: mike rehm doesn't own a pc, but he does just about everything, including his taxes, on his tablet. rehm is part of a growing wave of filers doing their taxes on a touch screen. he's one of more than six million turbotax customers who have already filed taxes on mobile devices this year, on track to double over last year. >> i still don't like to pay the taxes. however, it does make it a lot easier, a little more painless. >> you made some mistakes. >> reporter: gone are the dark images of doing your taxes or being overwhelmed by paper receipts. these days, people are buying more tablets and smartphones,

fewer pcs, and they're doing their taxes on mobile devices too, even in a place like a coffee shop. but just because you can doesn't mean you should. but with hackers these days looking to steal personal information, is it safe to file wirelessly? >> what people don't understand, there is no 100% way of making wireless secure. there is none. don't use open wifi. don't use wifi that is not under your control. and once it's done, make sure that you're securing your information somewhere else. do not leave it on that phone. >> reporter: have you ever lost customer tax data to a hacker? >> no. >> reporter: never? >> never. >> reporter: intuit's turbotax, the most popular tax software in the country, says they use the same encrypted technology as banks. accounts are password-protected and -- >> if you put your phone down and leave it unattended for eight minutes, we will automatically delete that information. but it is stored on our servers.

>> that one is good. >> reporter: mike rehm says the time he saves doing his taxes on his tablet makes it all worth it. >> doing it in the comfort of my own home makes me available to my daughter, to spend more time with her, to spend more time with my wife. >> reporter: even if he's not getting a refund this year. jon fortt, nbc news, new york. coming up, with predictions of one of the worst allergy seasons in years, it is too late to guard yourself against it?

♪ pope francis led palm sunday services today for a crowd of more than 100,000 worshipers at st. peter's square. for christians, palm sunday marks the beginning of holy week, culminating with the celebration of easter. after mass, the pope gave groups of young people something they'll always remember. he hopped off his popemobile to take selfies, including these with a group all the way from rio de janeiro. nasa has ordered a spacewalk to fix a computer outage on the international space station. two astronauts are now scheduled to step out into space next week to repair a backup computer for some robot systems. it failed on friday.

nasa assures the main computer is working just fine. experts say it's a direct result of our severe winter weather. what's being called the pollen vortex is expected to produce one of the worst allergy seasons in years. joining us tonight, dr. meika roberson, director of emergency medicine with carepoint health medical group in hoboken, new jersey. dr. roberson, how bad it is and how much worse it is going to get? >> well, they're saying it's going to be the worst allergy season in the past ten years. the trees and plants that have been dormant during this bad winter season in february and march will all have a huge surge of pollen right now. this pollen in the air will be such high counts that it will really affect the allergy sufferers. >> not good news for any of us who suffer from it. what can we do to get some relief? >> sure. well, severe allergy sufferers

should already have gotten the immunotherapy shots. so that should have happened about three to six months ago. that's when it really becomes effective is three to six months after the allergy shots. you should also go to your doctor, get skin tested, find out exactly what pollen you're allergic to, which trees, which grass, which mold. and then there are many over-the-counter remedies. there is many antihistamines and nasal sprays. other than that, there's just routine things you can do around your house. keep your windows closed. use the central air. when you're driving, keep the windows up. sunglasses, a big hat, all of that really help. >> bring on spring. dr. roberson, thank you so much for walking us through allergy season this spring. >> thank you. still ahead, the cross-country effort in honor of the boston bombing victims.

a photo shoot for a "sports illustrated" cover marking the first anniversary of the boston marathon bombings brought thousands of people to the marathon finish line yesterday. they included survivors, first responders, and city officials. the issue will be released wednesday, a day after the bombing anniversary. in boston tonight, an inspiring cross-country relay race just crossed another finish line. it was a race of endurance, teamwork, and most of all, sacrifice. the entire effort benefitting survivors of last year's attack. more now from nbc's ron mott in boston. >> reporter: in groups large and small, they ran. day or night, rain or shine, no matter, they ran. >> how are you feeling? >> amazing! >> reporter: through countless towns across america, they ran

for just one. one run for boston, for marathon survivors, an idea put into motion by three friends. this already the second such relay since the tragedy. >> the running community transcends international boundaries. and so for us, it hit us at the heart like so many other people. >> reporter: like kate, co-founder danny bent has been along for the ride the whole way, driving, running here and there, sleeping occasionally in runners' homes. >> we have to keep this going. really, we live off hope. >> reporter: the run began march 16th in santa monica, california, and coursed through 14 states, a 3,300-mile trek with more than 2,000 runners, recruited and tracked in realtime on facebook, raising money every footstep of the way, $400,000 and counting. >> you can make a left turn right here. all right. thank you. >> reporter: before dawn two days ago in central new jersey -- >> carry it for a little bit, man.

there you go. unbroken chain. >> reporter: stage 302 took off, bringing the torch nine miles closer to its destination. >> we all have a message that we're trying to send, but mine is through solidarity we can come together for a cause and make a difference. >> reporter: the difference for marathon survivors like john odom, on hand for the first stage in l.a. last month, is invaluable. wheelchair-bound for a while, he is back in boston for the final stretch with other survivors. >> the prayers and the support that they gave to me and my family. now i feel that i have to give back that to people that i see. >> reporter: tonight, they finished what theytarted, the goal of any race. though after last year it's become a goal never again taken for granted. ron mott, nbc news, boston. >> that is "nbc nightly news" for this sunday. brian williams will be here tomorrow. i'm carl quintanilla reporting from new york. for all of us here at nbc news,

good night. nbc bay area news begins with breaking news. >> we're actually following two breaking stories tonight. a major fire is burning right now at the site of the old kntv studios in san jose. it started at about 3:00 this afternoon. the other breaking story we're following is the arrest of 49ers linebacker aldon smith. new cell phone video appears to show officers taking smith into custody at l.a.x. we'll have more on what led to his arrest. good evening. i'm diane dwyer. we begin with that fire. flames and thick smoke could be seen for miles and san jose had to call for mutual aid from neighboring cities to help battle the names. in all about 100 firefighters responded to the scene. we have live team coverage with