some snow. if you want to call those high temperatures tomorrow 40s and 50s outside, we warm up toward next weekend. >> sounds great. "nbc nightly news" is next. more local news on the bay area at 6:00. we wseen. od boiling point. an explosion of fury in afghanistan. a u.s. base under siege and tonight an all-out manhunt for a killer of u.s. troops. record highs and soaring toward five bucks a gallon. what can be done to ease your pain at the pump. tax refund rip-off. tech savvy thieves stealing your money. tonight, how to make sure you get back what is rightfully yours. winter green. record warm weather and its boom-like benefits for families across america. and all together now. ♪ a chorus of strangers making musical magic.

captions paid for by nbc-universal television good evening. that anti-u.s. uprising in afghanistan turned violent for american troops again today. at least seven u.s. soldiers were injured in a grenade attack during a protest. it happened just one day after two american military advisers were murdered inside an afghan government compound in kabul. the revolt poses a worrisome new threat to the war that already claimed more than 1,900 american lives. and with 96,000 americans still in the country, many of them working side by side their afghan counterparts, it also threatens to shake the very underpinnings of the u.s. strategy there. andrea mitchell will give us the take from washington. but we begin in a snowy kabul where nbc's atia abawi has more on today's bloodshed. atia? >> reporter: good evening, lester. well, though there are fewer

protests today, there is still a great deal of anger here, primarily directed towards americans and other foreigners. six days on and the rage continues. in kunduz province, demonstrators targeted an american base today and in the chaos, someone threw a grenade, wounding at least seven u.s. soldiers. meanwhile, a manhunt is under way for the suspect in yesterday's killing of two high ranking american officers working inside the heavily fortified interior ministry in kabul. officials are looking for abdul saboor, described as a low level intelligence officer or driver at the ministry, who slipped away after the shootings. police have questioned his family. for his part, president hamid karzai went on tv today to offer condolences to the families of the slain americans, and to call again for an end to the protests over the burning of korans at a u.s. base. he said our emotions were shown all over the country regarding

this and it is now time to return to calm. the u.s. ambassador to afghanistan said today he believes the anger will eventually settle, and that the u.s. mission is still important. >> this is not the time to decide that we're done here. we have got to redouble our efforts, we have got to create a situation in which al qaeda is not coming back. >> reporter: after yesterday's attack, and the killing of two other u.s. soldiers on thursday, the commander of nato forces in afghanistan withdrew almost 200 military and civilian advisers from afghan ministries in kabul, citing concerns for their safety. >> we haven't had the impact on afghan security forces that we should. the fact that we're pulling people out of advisory roles in ministries in kabul, that demonstrates weakness. >> reporter: the united states has apologized repeatedly for the koran burnings, yet still the protests and the violence go on.

late today, one of the americans killed in yesterday's attack was identified. it was 44-year-old lieutenant colonel john loftus from kentucky and also tonight, the pentagon says a planned visit by afghanistan's defense and interior of ministers as well as other senior officials has been postponed. lester? >> atia abawi in kabul tonight, thanks. we want to bring in andrea mitchell, our chief foreign affairs correspondent. what is the level of worry over this in washington about the u.s. mission going forward? >> it is extreme because the eruption of this violence is really alarming. it undercuts the whole rationale for the u.s. mission in afghanistan, lester. suggesting that after all these years, the lives lost, the money spent, we still have not forged a real partnership of trust with the afghans who are supposed to be training them so they can carry on without us. now the prospect that an afghan intelligence officer could have murdered those two american officers, if that is proved, that will make it even worse.

our ambassador to afghanistan ryan crocker who you just saw in atia's report has also withdrawn embedded u.s. civilians. from afghan ministries, so it isn't just the military relationship with afghanistan that is being curtailed. there now is also going to be pressure on the white house to announce i think a more rapid withdraw from afghanistan when nato meets in chicago in may. and this is, of course, going to be a campaign issue. finally, we should point out that even though the burning of the korans was reportedly inadvertent and in no way justifies murdering americans, the military has to be asking itself how can that kind of mistake be made ten years into this war? lester? >> andrea mitchell in our washington newsroom, thank you. another hot spot tonight, syria, where the assad regime held a referendum on a new constitution. a desperate attempt to cling to power. that move being dismissed by secretary of state hillary clinton as a sham, a cynical ploy, she said, to justify the crackdown on dissent. meantime, the fighting continues and tonight dozens more are dead. we get our report from our chief foreign correspondent richard engel near the turkey/syria

border. >> reporter: lester, this referendum is effectively a yes/no vote on new articles of the syrian constitution, and amendments that, in principle, sound very good. they end the syrian baff party's monopoly on power, set term limits for the president, and implement multiparty democracy. the syrian government is presenting this as the centerpiece of its reform program, a program that has been called for by the syrian opposition and members of the international community. the problem is the syrian opposition has absolutely no confidence that any of these changes will actually be implemented. and the referendum is taking place amid ongoing violence. at least 20 more people were killed in syria today. the red cross has been unable to reach the hardest hit parts of the city of homs, so a referendum is taking place, but a war is taking place at the same time. lester? >> richard engel. tonight, legendary former south african leader nelson

mandela has been released from a hospital, and is resting comfortably at home. the 93-year-old mandela underwent some minor surgery after complaining of abdominal pain. though there was understandable concern due to his age, he's 93, south african president jacob zuma says doctors assured him there is nothing to worry about and that mandela is in good health. to presidential politics now. just 48 hours from that crucial primary in michigan where mitt romney was born and raised, tonight polls show romney and rick santorum neck and neck. and both candidates came out swinging today with a momentum of a race hanging in the balance. nbc's ron mott has our report. >> reporter: with the race for michigan zooming toward the finish line on tuesday, today, presidential politics moved to the fast track. mitt romney and rick santorum both showed up at the daytona 500. >> i'll vote for you. >> thank you. i need that. >> upstate new york. >> all right, we need your help. >> reporter: romney in person, in nascar red. santorum's red and blue logo on

the number 26 race car, which romney sized up. it was a sporting moment in an increasingly heated campaign, with fiery barbs flying in both directions in recent days and toward president obama. >> this president appeases. >> reporter: and though this race was postponed by rain, the other continued. santorum made the sunday talk show rounds this morning, hitting on romney's conservative claims. >> comes out here in these debates and tries to say he's the conservative in the race. it is a joke. >> reporter: defending his snob remark about the president, suggesting all americans give college a try, even going after in graphic detail the famed 1960 speech by john f. kennedy to protestant ministers. >> i believe in a president whose views on religion are his own private affair. >> reporter: a speech about separation of church and state. >> i don't believe in an america with a separation of church and state as absolute. people of faith have no role in the public square, you bet that makes you throw up. >> reporter: for mitt romney, who picked up an endorsement

from arizona's governor jan brewer in advance of that state's tuesday primary, connecting with the religious right has been a struggle. >> kim drives a couple of cadillacs actually. >> reporter: so too with blue collar republicans, like some of today's nascar fans, many of whom say romney is out of touch. >> you know, i can't be perfect. i just am who i am. if people think there is something wrong with being successful in america, they better vote for the other guy because i've been extraordinarily successful and i want to use that success and know how to help the american people. >> reporter: tonight, nbc news learned that rick santorum will get secret service protection beginning tomorrow on the campaign trail in michigan. former speaker newt gingrich has asked for secret service protection. governor chris christie reaffirmed he has no intentions of running for president at this time, but said he would list finance governor romney calls him about joining a fall ticket. lester? >> an interesting conversation going on, ron. thanks.

let's talk about it, we bring in our political director in chief white house correspondent chuck todd. what about this idea of someone else getting in late in the game, if romney loses michigan? >> well, we know there has been some chatter about it and some republican strategists have been looking at the different filing deadlines, what is realistic, this or that. it all does depend at this point on romney in michigan. if he loses michigan, that chatter will get very loud. you will hear public calls. you will hear public hand wringing. there is some united states senators in particular that have been talking about this without putting their name to it. they'll start putting their name to it. but it does -- at this point, you got to feel better today if you're mitt romney than last week, because it does feel he's got a little bit of momentum back, that he's probably inched ahead in michigan, and at this point barring a bunch of democrats coming over into this primary and that's very possible, michigan has a history of this, and putting santorum over the top, they feel a lot better today about sweeping michigan and arizona than they did two weeks ago. >> let me take you back to our lead story, this anti-american violence in afghanistan, both romney and santorum say today

the president shouldn't have apologized over the koran incident. you heard andrea say this could become a political issue. is this going to become the next political flashpoint in this election season? >> what i found fascinating is you had the third candidate here, newt gingrich, the other day saying if they're going to target, if the afghans and afghan forces are going to target american soldiers or nato soldiers, then maybe it is time to get out completely. so in whether it becomes an issue, i think what you're going to see is a public flashpoint about whether we have got a -- to speed up the withdrawal process from afghanistan, lester? >> chuck todd in our washington newsroom, thank you, chuck. now to what is sure to be a major issue on the campaign trail into the summer and fall. the skyrocketing price of gas. the average price of a gallon of gas in america is now $3.69, that's 30 cents more than it was just a month ago. cnbc's phil lebeau joins us now from chicago. phil, is there any end in sight to this rise? >> unfortunately there is not, lester. part of the shock and the outcry

we're hearing from people is because we have seen gas go up so quickly, 19 straight days gas prices have gone up. what we'll see from here, lester, is a repeat of 2008. people will drive less, more car pooling, people buying will migrate toward small cars, hybrids will become more popular. as far as the outlook for the future, unfortunately, lester, it looks as though we're going to see prices continue to go up. remember, the summer driving season, people drive more, there is greater consumption of gasoline, that's usually when we see gas prices going up. so unfortunately we're seeing this now in the spring which means we could be in for a costly couple of months this summer. >> not what we wanted to hear. phil, thank you very much. a program note, tomorrow, cnbc will have special all day coverage on gas prices. when "nbc nightly news" continues on this sunday evening, hundreds of thousands losing their tax refunds to thieves. how you can protect yourself. later, how a chorus of virtual strangers can sing in such perfect harmony.

it is only late february, but it is never too early for a lot of folks to start thinking about filing their tax returns. and this year we can add one more reason to get it done early. tech savvy thieves going after your money. as our justice correspondent pete williams reports tonight, if you don't file soon, someone else may end up getting the refund you're expecting. >> that's my baby. >> reporter: bart cohen, a retired miami police officer, only recently got his tax refund. not from this year, from last year, expecting a $4,000 refund, he was stunned to discover that someone else beat him to it. >> it is just a huge nightmare that you just can't believe it

is happening. >> reporter: it took months to straighten it out with the irs, all that time without his refund. >> i'm retired and disabled, so we live paycheck to paycheck. and it is important that the money is there for us. >> reporter: the crime of stealing someone's identity to get a tax refund from the irs has exploded, from nearly 49,000 cases two years ago to more than 260,000 a year now. last year alone, the irs says it stopped phony claims for $1.4 billion in refunds. in florida, police say it is sweeping the streets like a drug epidemic, entire rooms of people using tax filing software armed with stolen social security numbers, the key to the scam. with their piles of cash, they buy expensive cars, jewelry and clothes. the government says it is putting in more trip wires, such as name and address mismatches, but the deputy irs commissioner says it is hard to separate honest record changes from dishonest ones. >> millions of taxpayers move

every year. millions of taxpayers, you know, have children. millions of taxpayers change jobs. and so we have to go through the process of validating are you really who you say you are. >> reporter: the irs is also hoping to check returns against w-2 pay forms more quickly, something it doesn't do now until after refund checks go out. so how to protect yourself, the experts stress safeguarding your social security number above all. >> don't use it as a password. don't let companies use it as a log-in i.d. for you. never enter it on a website, no matter how many times a website asks you. protect that social security number like it is money because it is. >> reporter: and the most important tip, file early, so you get your refund before someone else does. pete williams, nbc news, washington. up next here tonight, how all this warm weather we have been seeing has created a new and welcome kind of winter wonderland.

we're back with a developing

story in ontario, canada. tonight, a passenger train derailment. at least three people are reported killed and emergency crews are working to rescue others from the wreckage. 75 people were on the train, which was traveling from niagara falls to toronto. despite a few cold snaps here and there, this winter is going down as the fourth warmest in 117 years. 80% of the country has had an above normal season. you can thank the jet stream that has been stuck in place, keeping cold air far to the north. that's been good news for city budgets, jobs and businesses big and small. we get the story tonight from nbc's tom costello. >> reporter: from 60 and 70 degree days along the east coast to the crowded links in the midwest, for much of the country it has been a snowless winter. for proof look no further than the piles of unused salt and idle plows in boston. by this time last year, boston had already dug out of 73 inches of snow.

so far this year, just 7 inches. of the $17 million it budgeted for snow removal, it used only $2 million. so rather than battle snow and ice, they declared war on another boston nemesis, potholes. >> so far this winter we filled about 2,500 potholes. we have used about 200 tons of asphalt. >> reporter: lots of cities have been saving money on plows and salt. by this time in february, new york has usually cleared 19 inches of snow. this season, it only had 7 inches. buffalo normally has 76 inches by now, this year, just 33 inches. chicago, normally 28 by now. this year, 19. minneapolis, 39 is normal. 18 inches this year. and fargo usually has had 36 inches. this year, just 16. fewer snow days mean more days on the job. construction crews at the new boston tea party ships and museum project are running ahead of schedule.

>> last year we lost over 25 working days. this year we lost three. with that translates into is real savings for owners on projects. >> reporter: it is happening across the country, 21,000 construction jobs added in january, 31,000 in december. and all those jobs helped bring the unemployment rate down. true, the season hasn't been kind to ski resorts, tow truck operators or folks who like to ice fish. but the weather channel's jim cantore says the warmup may be easier. >> we may not see the flooding we had last year on all three of the major rivers in this country. >> reporter: the bad news, expect a lot more bugs this spring, pollen too. but at jp licks ice cream, they're not complaining. >> we're busier, 20% up over last year. >> reporter: licking their way to a warm, profitable winter. tom costello, nbc news, boston. want to show you now some incredible images from high above the crippled fukushima daiichi nuclear power plant in japan.

our first look from a helicopter since the devastating tsunami last march. japanese officials have decided to scale back the no-fly zone from a 20 kilometer radius down to just about three miles because they say radioactive readings around the plant have dropped to a safe level. up next here tonight, altogether now, in the virtual -- in the most exquisite virtual harmony we have ever heard.

finally tonight, get ready for the kind of performance you may have never seen. no, we're not talking about the oscars. it is the power of the human voice, multiplied by thousands, all of them strangers, brought together by one man, a recent grammy winner who took his creative vision to the cyberstage. let's listen along with nbc's kristen dahlgren. ♪ >> reporter: the music is magic. but this is no traditional choir. ♪ it is thousands of individual singers, together only in cyberspace.

>> it is really bigger than my wildest dreams. >> reporter: eric whitacre is the man behind and in front of the virtual choir. a classical composer, with rock star appeal. whitacre got the idea three years ago. >> hi, mr. eric whitacre. >> reporter: when a 17-year-old from long island posted this to youtube. ♪ >> it hit me like a lightning bolt. i thought if i could somehow get 50 people to all learn their parts and then simply start their video at the same time, it would have to make a choir, right? >> reporter: it did, almost 200 singers sent in their clips. then the next year, more than 2,000 entries. >> you can see how committed he is. >> reporter: and this year, almost 3,800. >> she's from south africa. >> reporter: from 73 countries and all ages, the youngest 10-year-old jorjina harris. >> everybody can join in. even if they don't live near a choir, they can be part of one.

>> reporter: all you need is a computer. the singers follow whitacre conducting and everyone is accepted. >> if they go to the trouble of learning the music, uploading the video and joining the choir, absolutely. somehow when we put it all together, it comes to this incredible musical experience. >> reporter: and a community. >> you may be technically by yourself, but you're not. >> reporter: beth says it helped her through a serious illness. >> it is just amazing that these people from all over the world that i've never met care. ♪ >> reporter: and that may be the real beauty of the virtual choir, so many individuals, now joined together, even if they never see the person singing right next to them. >> that's the only motivation is just to be part of something and for it to be as good and as beautiful as possible. >> reporter: kristen dahlgren, nbc news, fullerton, california. and that's "nbc nightly news" for this sunday. brian williams will be here tomorrow. i'm lester holt reporting from new york.