on our broadcast tonight, outrage, the murder of a teenager that has become a national movement. new pressure on the police. and the part of the story that sounds so familiar to so many families. two steps forward. a big win at the polls, a big new endorsement, but it happened again. one step back for the romney campaign. the remark a top adviser might wish he could take back. mean season. the downside of early summer. why millions are suffering through this otherwise pleasant arrival of warm weather. saints and sinners. tonight, the shot hurt around the world of sports. and the boomtown. what is that shaking homes and nerves, keeping all the people up at night? the mystery in a small midwestern town. "nightly news" begins now.

good evening. they are driven by a social media campaign, by mainstream media coverage, by sadness, and just plain outrage at the thought that an innocent teenager was killed in cold blood outside of his father's home in florida. to show you the level of concern over this case in florida, this is a rally under way tonight here in new york. national attention has now come crashing down on the case of trayvon martin. he was 17 years old. he was encountered by a local neighborhood watch volunteer who unlike a lot of others in neighborhoods across this country, had a gun. he has not been arrested, and now that the feds and the media have swooped in on this case, the pressure is on. we begin tonight with ron allen in florida. >> reporter: with a grand jury

about to review the case, today, state investigators gathered potential evidence at the gated community where 17-year-old trayvon martin was gunned down 25 days ago by a neighborhood watchman. today, the police chief said his claim was supported by physical evidence and testimony. the orlando sentinel spoke to a witness. >> i looked and i saw someone lying on the ground, and i heard someone yelling for help. i heard the shot and right when i heard the shot, the screaming stopped. >> george zimmerman has not been charged in the shooting. neighbors said today they asked him to move out of his townhouse, and in an naacp forum, residents listed a long grievance of police treatment of young black men before the martin case. >> they put these black boys in jail and give the all kinds of bogus charges, and they're not true. >> enough is enough. we're sick and tired of it. >> reporter: the remarks will go

to justice department investigators in washington, and at that same meeting, sanford's mayor pledged to take action. >> i truly want everybody to know that i take this personally. i can't right the ship in one day obviously, i know there's a lot of tension. >> we as people of color are going to stand our ground. >> at a town hall meeting last night, residents expressed outrage about the so-called stand your ground law that police say justified the shooting. the 2005 law says deadly force is justified if someone believes that such force is necessary to prevent imminent death or great bodily harm. an author of the law said it should not apply in this case. >> there is nothing in this statute that authorizes someone to pursue and confront other people. >> all of that gives little comfort to martin's parents who continue their public plea for justice. this morning on "today."

>> i just hurt and my heart hurts because this guy has not been arrested. they decided on the scene to be the judge and jury. and i just want this guy arrested and so he can be brought to justice. >> reporter: also tonight here, police are saying for the first time that they believe that zimmerman did not confront and pursue martin. that zimmerman had returned to his car and was waiting for police and that martin, the teenager, attacked him. that's why they're sticking to their conclusion that zimmerman acted in self defense. brian? >> ron allen starting us off in sanford, florida, tonight. thanks. there's a lot of anger over this case and there's another angle to this case as well and it's personal. for a lot of black families across this country, this shooting hits close to home and reenforces a fear many say they quietly live with every day and have taught their kids about for generations. that part of this story tonight.

>> make sure all of the stuff is out of that back seat. >> wendy ealey-walker never met trayvon martin but feels like she knew him well. >> that could be my kid, minding his own business, doing his thing, not thinking that anybody would ever do him harm. >> like so many, this suburban atlanta mother is devastated by martin's death, and as a black parent, she worries his 14-year-old son could be targeted. >> it makes me angry and very frightened. >> reporter: a fear understood by many in the african-american community where it's common for parents to give their sons rules to live by beginning at a very young age. >> my mom told me go with what the cop says, don't argue with them, every time i'm at a public event or a cop sees me on the street. or a security officer sees me on the street, he asks me, where are you supposed to be, boy? you can sort of tell it's not the same treatment they give everyone else. >> one columnist called it the

"burden of black boys in america." >> you're constantly having to make psychological adjustments to watch the way your hands are moving, to watch your posture, to watch the way that your feet are moving to make sure that you don't make an abrupt movement. that may mean that you have to compromise a bit of your pride, but i want you back home alive. >> while what happened is still unclear, reports of martin's death have sparked outrage across the country. >> there is going to be something done about this. >> mark thomson's national show is flooded with calls. >> my heart is broken. >> people have literally called in and cried on air. i have even fought back some of my own tears. >> it's a manifestation of something that you feel, that you breathe all the time. that doesn't have a texture or doesn't have a mass but it's very real and always around you like air. >> a painful reminder for so many black families. >> see you later.

have a good day. love you. >> trayvon is not just his mom's kid. he's everyone's child. >> one 17-year-old's death giving an age-old fear a new face. >> now we switch to the presidential campaign trail where on the heels of a big win in illinois just last night, mitt romney's campaign found itself once again fending off the damage from a self-inflicted wound. specifically a quote they would like to have back right about now. our report tonight from chuck todd. >> reporter: it was one of the big republican endorsements mitt romney craved, but former florida governor jeb bush's statement in the wake of the decisive illinois primary win came on paper. now is the time for republicans to unite behind governor romney. and it lacked the enthusiasm and pump that characterized some others. still, bush's signal that romney's nomination is inevitable was exactly the message team romney hoped would

drive the day, but like some other memorable flubs. after big primary victories -- >> i like being able to fire people. >> i'm not concerned about the very poor. >> a gaffe rained on the parade. in this case, it was eric fernstrom's response to whether romney's more conservative stances in the primary will hurt him in november. >> you hit a reset button for the fall campaign. everything changes. it's almost like an etch-a-sketch. you can shake it up and we start all over again. >> by lunchtime, etch-a-sketch was viral. a democratic operative had tweeted a romney caricature inside the classic red toy. soon after, the dnc was out with a new web video. by afternoon, newt gingrich and rick santorum was using actual etch-a-sketches as props. >> to have his communications director say to all of us, if we're dumb enough to nominate him, we should expect by the

acceptance speech we'll move back to the left, triggers everything we're worried about. >> santorum's campaign even sent an aide to romney's lone campaign event of the day to hand out etch-a-sketches. romney brushed away a reporter's guess before submitting to one at a hastily called press avail. >> a campaign takes on a different profile. the issues i'm running on will be exactly the same. >> you know, while romney did hope to add the words presumptive nominee in front of his name today, the campaign even before etch-a-sketch had one eye on santorum. their daily attack e-mail went out, and of course, the super pac has negative ads running in wisconsin, the next big fight. >> proof again anything can happen in politics. chuck todd in our d.c. newsroom. chuck, thanks. overseas, a dramatic standoff all day long in france where riot police cornered the gunman who admits, boasting that he's responsible for killing seven people in three different terror sprees.

jim maceda has the latest on the standoff in toulouse and more on the man who said he wanted to bring the nation of france to its knees. >> inside this house in north toulouse, the gunman who alle d allegedly killed soldiers and civilians, muslims and jews, and outside, hundreds of special police hoping to avoid a blood bath. an early morning police raid, the suspect put up stiff resistance. three policemen wounded in a barrage of gun fire. this neighbor's son was scared awake. >> i was with him on the phone, a grenade exploded, he dropped the phone. he must have been terrified, he said. >> the gunman, 24-year-old mohammed merah, wanted to talk. he bragged about how and why he killed three french soldiers last week because they served in occupied afghanistan. his victims in a jewish school, a rabbi and three children, revenge for the murder of palestinian children. he swore allegiance to al qaeda and said he trained in militant

camps during several trips to pakistan where french police first took notice of him. home grown and hard core. >> he obviously had done some reconnaissance. he wasn't just going out looking for likely targets. in the way that a deranged gunman does. >> but it was his get-away scooter like this one that was his undoing. a suspicious motor bike shop keeper tipped off police after merah asked for advice on how to deactivate its built-in tracking device. news that the shooter was cornered brought relief, but there was great sadness, too, at the targeted jewish school which reopened today. in jerusalem where the four victims were buried, and here in france where the french soldiers were laid to rest. and we have just heard 3 large explosions, they could have been stun grenades, flash back, or

worse. what we're hearing is that negotiations are over and the assault on the house and the gunman has truly begun. back to you, brian. >> jim maceda, toulouse, france. thanks. >> there's news to report in the investigation into the massacre in afghanistan allegedly committed by the american staff sergeant and reports that afghan villagers have been offering one theory about what might have motivated his rampage. our pentagon correspondent jim miklaszewski on duty from there tonight. jim, good evening. >> good evening, brian. another twist to the tragic story, villagers where the shooting took place are now claiming that the 16 civilians were gunned down in retaliation for an ied attack against american forces. they claim days before the massacre, american combat troops entered the village and threatened to kill every man and their children for that attack on the americans. but pentagon and military officials said there's no evidence of any ied attack around that time and no evidence

the americans threatened retaliation. in fact, officials here at the pentagon suspect this is nothing more than propaganda. at the same time, we're told tonight those charges against the suspect, army staff sergeant robert bales, including 16 counts of murder, are expected at the end of this week. >> jim miklaszewski from the pentagon tonight. thanks, as always. still ahead as "nightly news" continues, ahead of schedule, not always as nice as it looks, though. warm weather is triggering misery for millions of americans. and later, sleepless in a small town. why the people who live there are desperate for the mystery noise to stop.

we have been reporting for days on end about the freakish warm weather that has enveloped so much of the country so early in the season, like 85 degrees in chicago, but of course, there are downsides, especially for the 60 million americans who suffer from allergies. our report tonight from nbc's chris jansing. >> in atlanta, it's never been this bad. allergies are sending sufferers to the doctor. >> my nodes nodes is really stuff a. >> drivers to car wash. yesterday, pollen counts broke all records. >> i have never seen anything like this. we're seeing patients coming in with terrible symptoms. >> this machine quantifies pollen in the air, typical this time of year, a reading of 2000.

the new record, dangerously high, almost 9,400. the same story playing out across huge swaths of the country. this forecast predicts medium to high pollen counts for at least the next four days. they're seeing it in chattanooga. >> i just washed my car. it was covered in yellow ick. >> and feeling it in charlotte. >> just really stuffy. >> both have the dubious distinction of being among the worst cities for spring allergies. gorgeous trees like this are among the culprits. first a warm winter now record high spring temperatures which means the pollen is released much sooner and there's much more of it. not all pollen is created equal. pine tree pollen acts like dust and can build up on your car, but far worse for many allergy sufferers is microscopic oak tree pollen. this year, it's affecting patients that have never been affected before, and all this misery can have serious consequences for people with asthma.

this suburban atlanta school may have just the right idea, close doors and windows tight to keep the pollen out. experts say common sense like staying indoors and over the counter medications can go a long way. though this year, more of us may need a trip to the doctor because what looks so good can feel really bad. up next here tonight, the sports world blows up after what happened today, after hard hits, a legendary team is getting hit hard.

there's a huge sports story in the news tonight. the nfl has come crashing down on one of the great and storied football teams of all of football. the new orleans saints will pay a heavy price and perhaps for years to come for a system of player bonuses, bounties paid to players, up to $1,500 for taking an opposing player out of the game. they learned today their coach sean payton has been suspended

for a year. they'll lose two draft picks. other coaches will be sidelined including the general manager, and they'll pay a $500,000 fine. we get reaction tonight from ben ryder of sports illustrated and si.com. >> the impact on the saints is going to be enormous. they've gone from kind of america's sweethearts and super bowl champions of two years ago to now the villains of the nfl. they're going to have real competitive issues. they were cheating to a degree. however, here we're looking at players who are paid to go out and do damage on opposing quarterbacks, and we're punishing them for their team paying them to go out and do damage to opposing quarterbacks. something doesn't entirely add up. yes, it was against to rules to run the bounty system, some punishment should be meted out, by commissioner roger goodell, however, the sheer immensity of the punishment shows there's more at work here. it's really about the image of the sport. this is a public relations move

more than anything, i think. we like to think of football being a sport of honor. it's a really gray area when you think about it. when does hitting someone become trying to injure them? however, this struck a nerve in the public. it has discredited the nfl, tarnished its image. that's why the office came down hard on the saints. >> ben ryder of "si "on today's big story. there were high honors today for a woman who is now the longest serving woman in congressional history, maryland senator barbara mikulski, first elected to the house in 1976, one of 21 women in congress back then. today, the veteran democrat is among 91 women in congress. there were some familiar faces at the new york stock exchange this morning, members of the cast of "mad men" along with their executives rang the opening bell. the series resumes after a 17-month hiatus on sunday night. for the true "mad men" addicts, even just the curious, we have a

preview tonight, including an interview with the creator and a rare look around the prop department for our cameras tonight on rock center at 10:00, 9:00 central right here on this station. up next tonight, the town dealing with the mystery noise.

finally tonight, a story about a nice place they're calling a boomtown, jokingly. the problem is it's not funny. the good people in one town in wisconsin would right now give anything to find out what is making that noise. their story tonight from nbc's kevin tibbles. >> reporter: in whats youed to be sleepy clintonville, wisconsin, something is going boom in the night. >> it was almost like someone took a wrecking ball do the side of the house. >> problem is, no one in the town of 4,600 west of green bay seems to know what it is. >> i thought a car was coming through my house, it was that loud. >> for three nights running, residents have been shaken and awaken. all these dots represent 365 residents reporting booms. >> i don't know what it is. >> we have some weird banging going on and our whole house is shaking. >> while it's a serious situation, in fairness to the

citizens, people are trying to have a little bit of fun with it. >> and the twitter sphere reverberated. >> what are the booms in clintonville, wisconsin. >> i have no idea they were filming the "trembles" remake in clintonville. >> they're under the ground. >> this may sound familiar. in the 1995 sci-fi spoof, tremors, aliens shake up a town in nevada. 2,000 miles from clintonville, wisconsin. >> no richter scale can measure it. no scientist can explain it. >> scientists seem to know what it isn't. it's not an earthquake or underground explosion or exploding gas, or electrical problem or even burping sewer system, and not a frost quake caused by unseasonably warm temperatures. so far, experts are stumped as to what it is. >> their whole lives are being disrupted by this, and we don't have a good answer for them. >> so tonight, the mystery continues as to why clintonville has become boomtown usa.

kevin tibbles, nbc news, chicago. >> we'll let you know. that's our broadcast on a wednesday night. thank you for being here with us. hope to see you later tonight for rock center. i'm brian williams, and we hope to see you right back here tomorrow evening. good nig good evening. i'm garvin thomas in for raj mathai. >> and i'm jessica aguirre. the east bay prosecutor whose arrest on rape charges rocked costa county rocked them tonight. he has never spoken at length about the case until now. jodi hernandez sat down with him. he is seeking justice