on our broadcast tonight, closing arguments in the george zimmerman case and fireworks in the courtroom as prosecutors make a late move that defense has called outrageous. weighing the risks of fish oil. we've been told for years it's good for your heart. but tonight, alarming questions about a link to cancer. a big break in one of the most famous criminal cases in american history. after 50 years, did modern science just reveal the boston strangler? "nightly news" begins now. good evening. the prosecution has now made its closing argument in the closely watched and highly charged trial of george zimmerman. he's been charged with second degree murder in the death of

trayvon martin, but that charge became an issue in court today. the jury now allowed to consider a lesser charge of manslaughter. the parents of the defendant and the dead teenager were all in court together for the first time since opening statements as final moments are getting close. the jury could have this case as soon as tomorrow. ron mott starts us off tonight from sanford, florida. good evening. >> brian, good evening to you. a hush fell over the courtroom as the prosecutor began the closing arguments that went on for more than two hours. at one point it looked as though he got a real reaction from george zimmerman himself. >> a teenager is dead. he is dead through no fault of his own. he is dead because another man made assumptions. >> reporter: the state started its closing today in a less

explosive fashion than it opened 17 days ago. >> [ bleep ] punks. these [ bleep ]s, they always get away. >> reporter: but made the same argument about trayvon martin's killing to the all-woman jury. >> the man who is guilty of second-degree murder. >> reporter: that george zimmerman should go to prison for profiling, following and shooting trayvon martin. >> why does he get out of the car if he thinks trayvon martin is a threat to him? why? why? he's got a gun. he's got the equalizer. >> reporter: with zimmerman's mart tip's parents all in court for the first time -- >> [ bleep ] always get away. >> reporter: the prosecutor said zimmerman sized up martin after a call to police. >> i will submit to you that he uttered it under his breath, and that itself indicates ill will and hatred. >> reporter: and for the second straight day. >> he is saying armpit -- how does he get the gun out? >> reporter: the state's

life-sized foam dummy was thrown into the mix. >> did you see where he's pointing to? did you see where he's grabbing, where he's got his firearm? >> reporter: and the prosecutor questioning the struggle with martin. >> this was never an easy case for the prosecution. it seemed to get more difficult every day of trial. while the closing argument seemed effective, it may not be enough for the crime of murder. >> reporter: earlier, sparks flew as both sides sparred over adding charges of lesser charges of manslaughter and third-degree felony murder. >> doesn't the court realize this was a trick by the state. >> reporter: the defense complained about getting notice of the third degree murder charge just this morning. >> just when i thought the case couldn't get any more bizarre, the state is seeking third degree murder based on child abuse? >> reporter: martin was 17 when he was killed. the judge denied the third degree murder charge, but said the jury may consider manslaughter in lieu of second-degree murder murder. zimmerman's attorney objected to any lesser charge. >> and you are in agreement with that? >> yes.

>> reporter: zimmerman pleaded not guilty to second degree murder. saying he shot martin in self-defense. >> the state has charged him with second-degree murder. they should be required to prove it, if they can. and if they can't prove it, that is the failing of the prosecution. >> reporter: tomorrow morning, the defense will make its closing arguments followed by a state rebuttal. and unless something unforeseen happens, brian, the jury is expected to be charged by the afternoon. ron mott has been covering through sanford, florida, starting us off tonight. 59 this point, let's bring in nbc news legal analyst lisa bloom who has handled some high-profile case herself. these are called lessers, lesser charges. does the introduction of manslaughter mean that the prosecution has less than full confidence in the case? >> well, certainly the side that is willing to take an all or nothing approach is the side that is more confident, and that's the defense. on the prosecution side, they'll be happy with a compromised verdict of manslaughter if they

can get it. i think if they get manslaughter or second-degree murder, they're going to consider that a win. >> all right, lisa bloom. we'll be keeping in close touch with this. again, the end of this case is rapidly approaching. we now head to san francisco where we are hearing the first 911 calls from the passengers on board the 777 aircraft in the moments after impact, after it had come to a halt on the runway and before it was consumed by fire. many passengers pulled out their phones because they weren't getting the help they needed. tom costello remains at the scene tonight for us. tom, good evening. >> reporter: hi, brian. the ntsb has just said it has plans to start cutting up the fuselage of this plane and removing it tonight. it hopes that by the morning the biggest pieces are out of here and headed to a warehouse. the preliminary data suggests that the autopilot, auto throttle, and flight director systems were all working properly at the time of the crash. the 911 calls you mentioned?

chilling as passengers plead for medics and ambulances. >> our airplane just crashed. >> there are a bunch of people who still need help. we're more out on the field where planes are landing. >> reporter: the first calls to 911 from panicked passengers who just escaped their burning plane. >> we have people over here who weren't found and they are burned really badly. there is a woman out here on the street, on the runway, who is pretty much burned very severely on the head and we don't know what to do. she is severely burned, and she will probably die soon if we don't get help. >> reporter: as firefighters fought the fire, commanders kept ambulances back at first, concerned the plane might explode. >> there are people laying on the tarmac with critical injuries, head injuries. we're almost losing a woman here! >> reporter: medics had their hands full. 180 injured. wednesday evening, about 70 crash victims and family members were escorted to the crash scene. each went for their own reasons.

now the seat belts inside the asiana 777 are getting attention. >> was pretty beat up. had a neck collar on. >> reporter: at st. mary's medical center, spine surgeon dimitri operated on a 70-year-old victim from china who suffered four neck and spine fractures and damage to his spinal cord. he was sitting in the economy seats with his lap seat belt on. like many passengers, he was slammed into the seat in front of him. but some passengers in business class had three-point seat belts like those used in cars. some of those passengers walked away unharmed. would shoulder belts have prevented the spine injuries? >> i do think it would have protected at least three of the four injuries that he has. >> reporter: on the runway today, crews began removing the wreckage of flight 214. sfo hopes to reopen 28 left sunday or monday. >> they will have to sweep and clean the runway, repair the pavement and the lighting. it will be up to the airport on when to get the runway back open. >> reporter: back to the

shoulder belt/lap belt issue. some airlines in the world use them in business and first class because the seat in front of the passenger may be too far away to provide protection. u.s. airlines have said if you're wearing a shoulder belt, you can't assume the brace position. the ntsb several years ago recommended shoulder belts in private aviation. they say it could cut the injury rate by 50%, but they did not make that recommendation for commercial aircraft. brian? >> tom costello in telephone for us tonight, tom, thanks. lots of extreme and torrential weather. flash flooding and a muddy washout in colorado springs. it happened last night. 20 or more vehicles swept off the road or stuck all in an area left scorched and barren by a wildfire last year, leaving it prone to this kind of flash flooding. there has been at long last a big break tonight in the murder case that received national attention as it gripped the city of boston half a

century ago. he was known as the boston strangler, and tonight it appears science may have finally caught up with him. we get the story tonight from nbc's katy tur. >> reporter: 50 years ago, boston was held hostage. >> evidence so far is skimpy. >> reporter: 11 women, most sexually assaulted, found dead in their homes. >> there is fear in boston. >> there was never really an end to that story. it was always lingering in the air for several years. who was it? was he still out there? >> reporter: albert de salvo confessed to the murders, but was never convicted and doubts surrounded his claims. he died in prison in 1973. >> a genuine murder mystery and the reopening of the boston strangler. >> reporter: in 1999, police hoped dna from the last victim would prove desalvo did it. it did not. today, new advanced testing will prove he was sullivan's killer.

>> these results are unprecedented in the history of this case. for the first time ever, law enforcement has a piece of evidence to test against a suspect. >> reporter: the suffolk d.a. says they were able to take dna evidence from 50 years ago collected right here at mary sullivan's apartment and then cross reference it with dna from a member of desalvo's family, and that's how they found a match. police are 99.9% positive, but will exhume de salvo's body to be sure. elaine sharp represents the desalvo family. >> just because you find dna that matches somebody on their body doesn't mean they murdered them. >> reporter: for mary sullivan's nephew casey sherman, it's as close to closure as he may ever get. >> it's amazing to me today that people really did care about what happened to my aunt, a 19-year-old gaurl heinously murdered in 1964.

>> reporter: katy tur. today in washington, two of the most powerful men in american politics, majority leader and minority leader of the u.s. senate, harry reid and mitch mcconnell, went at each other in the senate chamber. while their remarks were couched in the gooey and formal parlance of the senate, each calling each other my friend while attacking each other, today's exchange by these two men who bear the full share of the blame of how cancerous and politicized washington has become is a lesson in what goes on in the u.s. senate. and here is what happened today when mcconnell took on reid's threat to change the filibuster rules to stop republicans from blocking so many democratic nominees. >> this is really a sad, sad day for the united states senate. and if we don't pull back from the brink here, my friend, the majority leader is going to be remembered as the worst leader of the senate ever. >> i don't want him to feel sorry for a senate, certainly not for me. i'm going to continue to try to speak in a tone that is

appropriate. name calling -- i guess he follows -- i hope not, the demagogic theory that the more you say something false, people start believing it. >> again, the democrats haven't decided whether they're going to do this. they're just debating it for now. both men will appear on "meet the press" this coming sunday morning. still ahead for us tonight, fish oil is in the news tonight. millions of us have been told by our doctors to take it for heart health. but now they are raising serious questions about a possible link to cancer.

we are back with the story we mentioned from tonight's medical news. it will reverberate in a lot of american households. because the chances are you or someone you know is consuming more fish oil these days to protect the heart, whether it's from fish oil supplements or just by eating more of the right types of fish. well, today we learned of a big potential downside for some men who are getting high amounts of

fish oil in their system, and that's an increased risk of prostate cancer. we get the story tonight from our chief medical editor dr. nancy snyderman. >> reporter: researchers followed more than 2,000 men over the age of 50 who did not have prostate cancer when the study began. blood from each man was stored for analysis. at the conclusion of the trial, men who started with the highest blood levels of omega 3 fatty acids, the type found in fatty fish and fir oil supplements had a 71% increased risk of developing a deadly form of prostate cancer. researchers said they did not expect this link. >> inflammation we know is associated with the development of prostate cancer, and omega 3 fatty acids decrease inflammation. but this was an association but in the opposite direction we expected. >> reporter: today's report is a confusing message for millions of men like 54-year-old bill ross who take fish oil supplements to protect his heart. confusion, because bill also has a family history of prostate

cancer. >> my father is a prostate cancer survivor. he's been battling prostate cancer now for about 20 years. and so, you know, i'm at risk. >> reporter: conventual wisdom for years has been that fish oil protects against cancer and heart disease. >> i want to go over your labs with you. >> reporter: but cardiologists say you don't need fish oil supplements, and that a good diet with two or three servings of oily fish two or three times a week is enough. >> i am never a proponent of supplements. we've learned time and time again that more is not necessarily better. when we look at studies that look at the intake of foods high in omega 3 fatty acids, high in antioxidants, high in folate, we consistently see protection for chronic diseases like heart disease and cancer. >> reporter: the council for responsible nutrition, the leading trade association representing the dietary supplement industry calls the study overblown. the study demonstrates no cause and effect, it can only purport to show an association between

higher plasma levels of omega 3 fatty acids and those whom the researchers advise had an increased rate of prostate cancer. there is no doubt that this study is disruptive. it has people talking. but in the meantime, the american heart association is urging people to get their omega 3 fatsy acids from their food, and that means the right kind of fish. fatty fish like salmon, mackerel, herring, at least three times a week. and brian, i think as the doctor said, too much of a good thing can be too much for the human body. nonetheless, people are going to keep talking about this one. it has doctors talking. >> dr. nancy snyderman, thank you for the report tonight. up next, an original who provided many awkward moments over the decades in this country.

twister! milton bradley has a new one,

it's the twister! >> it is the game that provided more truly awkward body part innovations in more homes than any other because of the recent era. because of commands like right hand red. the inventor of twister has died. his name, chuck foley. he was from the twin cities. he set out to invent a game that would light up a party, and he succeeded. it was originally called pretzel, and milton bradley renamed it twister. and then johnny carson helped make the new game a sensation on "the tonight show" back in 1966. the father of twister, chuck foley, was 82 years old. a setback for the condition of randy travis, already hospitalized in texas and in critical condition with a heart infection. he has now suffered a stroke and had surgery as a result. randy travis is 54 years old. there is a report out of russia that the kremlin is looking to purchase typewriters and return to typed paper documents for their most

valuable secrets. after so many hacks and what we've all learned about the perils of electronic communications and privacy, the kremlin is apparently looking to leave the fewest possible traces, and that just might be keys striking a paper page. well, the folks whose job it is to clean up the public spaces at death valley have a request of all visitors. please stop trying to fry an egg on the sidewalk. they say it's making a big mess in the park in terms of residual goo and eggshells. they say if you must try it, use a skillet. but perhaps the best course of action for all of us is let's just keep using it as an expression without feeling the need to act it out. it's so hot you could cry an egg on the sidewalk. when we come back, how it helps to have an extraordinary attitude on the long road to recovery.

finally tonight, our conversation in boston just yesterday with boston marathon bombing victim, jeff bauman, it's now been almost three months exactly since that awful day and that awful scene. before we knew the name of either man, we first saw bauman as the young man being kept alive by the guy alongside of him, the cowboy hat.

we didn't know them yet, we do now. they've become close and spoken every day since then. and their bond is readily apparent when they get together. >> he was the one that picked me up off the ground. >> reporter: these two men were thrown together by fate in a moment preserved forever in a graphic and gripping photo that showed carlos arredondo keeping jeff alive as the life threatened to drain from his body. his life was saved, and a friendship was born. and without him, there is no you. >> no. and many others as well. >> a lot of great people helped me out that day. >> reporter: out there was boylston street. jeff was a spectator. his girlfriend was in the race. carlos, a costa rican born peace activist who lost two sons, one to suicide, the other in combat in iraq. and the two men now mean the world to one another.

>> every time i see him, he is so uplifting, so concerned with how i'm doing, how i'm feeling. he's amazing. >> i'm so glad i'm seeing this beautiful young man healing so well, you know, with the support of family and friends. >> reporter: and this being boston, there is such a thing as sports therapy. and let's talk, because sports is important in life. because your bruins had a great year. sox, we'll see. and the patriots, we'll see. >> sox are first. >> i know, i know, but it's early. it's july. jeff got to throw out the first pitch at fenway and was invited on hallowed ice at a bruins game. >> seeing like 20,000 people yelling for you and clapping, it's pretty intense. >> reporter: just three weeks ago, jeff took his first steps with the help of his new prosthetics. >> reporter: what have you learned about the resilience of the human body? >> it's crazy. it's really tough. it's insane. i mean, i'm a quick healer. they were calling me wolverine,

that guy that heals really quick. >> reporter: how do you remain so positive about your recovery? >> i just figure you can't be negative about it. why sit and be negative and be sad and depressed. you've got to push everything to the side and just focus on just getting better. >> reporter: his attitude is astoundingly positive, always pushing forward, always looking forward, and the people who have cheered him on, strangers, ordinary americans, have made an enormous difference. >> i love reading the letters. someone actually took time out of their day and thought about writing a hand-written letter to me. it just shows how great people are. >> an incredible story of grit and perseverance from boston. one of so many since the bombing again three months ago. that is our broadcast on a thursday night. thank you, as always, for being here with us. i'm brian williams. we hope to see you right back here tomorrow evening. good night.

nbc bay area news starts now. good evening, thanks for joining us. >> no back pay, no payout. the san jose arbitration union has lost its fight over benefits. the city says the decision will keep libraries open, but cops say the desis could mean an exodus of experienced officers. nbc bay area first broke the story last woke. what the city says, it still

want does negotiate? >> reporter: that's right. the mayor told me the 10% raise is still on the table, but the union says it's not really 10%. today we spoke with a veteran officer who said he's had enough. the homicide investigation team has had its hands full in san jose. and in these crime scenes is where you'll find this dent. >> the phone rings at all times of the day. >> reporter: but he says he's not picked up the phone and asked other departments if they want to hire him. capping vacation payouts. and the arbitrator ruled they can't have back the 10% in salary they gave up two years ago to help the city balancity books. >> if it was an emotional decision for me i would stay. but it's not emotional. i would b