what he's saying as the outrage boils over. "nightly news" begins right now. >> announcer: from nbc news world headquarters in new york this is "nbc nightly news with lester holt." good evening. it is one of the greatest mysteries of our time. the fate of malaysia air flight 370 and the 239 people aboard. tonight many are holding their breath wondering if it's finally on the verge of being solved. video and photos of a large piece of plane wreckage found on a remote yienltdisland in the indian ocean are carefully being scrutinized. we should tell you from the start not all experts agree but investigators believe the debris in the images is consistent with a boeing 777 the smam as the missing malaysian jet. nbc's tom costello has been working the story all day. what do we know? >> reporter: lots of phone calls. and sources tell nbc news that boeing investigators have looked at the photo and they believe it is in fact a piece of a wing perhaps a flap from a boeing 777. there's only one boeing 777 that's missing in the world right now. that is malaysia flight 370, missing since march of 2014. it's a huge break in the biggest aviation mystery in decades. sources tell nbc news that boeing investigators have looked at photos of the debris covered in sea shells and washed ashore on a remote island in the indian ocean. their conclusion -- it is in fact debris from mh370. it appears to be the flap from a wing, and police say it appears to have been in the water for at least a year. >> translator: investigation has started. so we're going to try to investigate to try and find out where and whom owns this piece of wreckage. at the moment we don't know. >> reporter: malaysia flight 370 with 239 people on board has been missing since leaving kuala lumpur in march 2014. reunion lies nearly 600 miles off the coast of madagascar but more than 4,000 miles from malaysia 370's last known location south of vietnam and thousands of miles from the remote southern indian ocean where underwater search teams have concentrated their efforts for roughly 15 months. treacherous seas have made that search zone extremely difficult. >> the question is how long has this part been sitting on that island? and somebody's going to have to really reverse engineer the flow pattern of the ocean and try and backtrack where this may have floated from. >> reporter: oceanographers say much of the indian ocean moves in a counterclockwise motion that could pick up debris and drop it on the other side of the ocean. so the question is whether that is what happened. french investigators on the island are working closely with investigators from boeing as well as australia and malaysia. they now have a huge challenge, as greg mentioned, trying to determine how long that wing flap may have been sitting on the beach then calculating the ocean currents to determine how far it might have traveled in the indian ocean. but lester at least we now know that malaysia 370 did go down somewhere in the indian ocean. we don't know why and we don't know exactly where. >> and tom, i'm curious what it may tell us. i know it's one piece, there's no black box that's been recovered. but might they at least be able to tell us whether the plane broke up in flight or maybe this piece came off during an impact with the water? >> i talked to an aviation expert and former airline captain john cox today. he said when you look at the photograph it does not look to him like it was violently ripped from the fuselage. he thinks that it may indicate it was more of a softer crash landing if that's possible. but also take a note of how much sea life was on the inside and outside of that plane -- the wing rather. that will give experts some clue as to perhaps where that sea life originated. they've got an awful lot of forensic work to do here. >> remarkable story. tom, thank you. the call for justice in the wake of the fatal shooting of an unarmed black man by a white ohio police officer was answered quickly and firmly. a murder indictment handed down today against a university of cincinnati police officer ten days after he shot and killed a motorist he had pulled over for a missing license plate. that officer turning himself in tonight and for the first time we are seeing the tape of the encounter. and we'll warn you, it is not easy to watch. here's nbc's anne thompson. >> reporter: the final moments of 43-year-old sam dubose's life captured on the body camera of the officer now accused of his murder. >> hi. how's it going? >> good. officer tensing, university police. do you have a license on you? >> no. >> reporter: ten days ago university of cincinnati officer ray tensing stopped dubose for not having a front license plate. he said it's in the glove box. >> you don't have to reach for it. it's okay. do you have a license on you? >> reporter: dubose doesn't produce his license. >> what's that bottle on the floor there? >> it's a bottle of air freshener. >> reporter: the bottle says gin but dubose insists it holds no liquor. several more times tensing asked dubose for his license and then something happens. >> okay. i'm trying to figure out if you have a license or not. go ahead and take your seat belt off for me. >> i didn't even do nothing. >> go ahead and take your seat belt off. stop. stop! >> reporter: less than two minutes after tensing approached tensing fires a single shot hitting dubose in the head killing dubose as the car starts to move. tensing chases after the car and another officer arrives. >> he purposely killed him. >> reporter: in the bluntest of terms hamilton county prosecutor joe deters called dubose's death senseless. >> this is the most asinine act i've ever seen a police officer make. he wasn't dealing with someone who was wanted for murder. okay? he was dealing with someone who didn't have a front license plate. >> reporter: the video appears to contradict tensing's story, that he was being dragged by the car and had to fire his weapon. tensing's attorney says there is a second tape that shows his client was on the ground. >> that he felt like his life was in danger. >> reporter: tensing is 25. he's been an officer for four years. full-time with the university of cincinnati since last year. the stop was made off campus but allowed under a mutual agreement with the city. for the dubose family -- >> seeing that video let me know this -- my son did absolutely nothing. >> reporter: both the dubose family and city officials are calling for calm. to avoid a repeat of the riots in 2001 after an officer shot and killed an unarmed black man. a videotape and today's swift indictment to keep the focus on justice in the death of sam dubose. anne thompson nbc news. >> without the video from that body camera the officer was wearing chances are we'd never know what the prosecutor says happened. the officer's word would be the end of the story. but body cams are changing the face of police investigations as we've known them. used to protect both suspects and the officers themselves as nbc's miguel almaguer reports. >> reporter: more than 6,000 police departments wear them nationwide. [ siren ] in cities big and small, body cameras are rolling on the mundane and meaningful. >> how's it going, man? >> reporter: in cincinnati samuel dubose's family says this video didn't just capture the shooting now it can lead to justice. >> stop. stop! >> we knew the video was going to vindicate our brother. >> reporter: police in los angeles have been using the cameras for months. at least one officer was wearing a body camera during a shooting in which some witnesses say a suspect reached for an officer's gun while others say he didn't. police chief charlie beck says it's an important step forward. >> body cams will make policing you know more accountable. but it also makes the public more accountable. >> reporter: the body cameras, still in a pilot program here at lapd are worn by 33 officers at roughly chest high. once they're activated by the officer, it starts recording. this is the view. the camera able to record hours of standard definition video and audio. in seattle it's public. >> vuft advise you're being audio and video recorded. okay? >> reporter: they're posting the videos on youtube. many redacted. but the goal is transparency to build public trust. >> it is an important piece of evidence that may allow us to come to the truth of what happens on the street. >> reporter: a step toward the truth, bringing closure for some perhaps justice for others. miguel almaguer nbc news los angeles. there is confirmation this evening on the report we woke up to this morning. the death of a leader of the taliban, mullah omar the one-eyed cleric who harbored osama bin laden in afghanistan as he plotted the 9/11 attacks and then defiantly refused to give him up sparking the 2001 u.s. invasion. afghan officials said today mullah omar died of hepatitis in 2013 but his death was kept secret by the taliban for more than two years. in colorado family members are pleading for the life of convicted movie theater killer james holmes. after sitting in silence for months, listening to witnesses describe the horror of holmes's crimes his parents took the stand today hoping to spare him the death penalty. nbc's jacob rascon has the details. >> i still love my son. yes. >> reporter: the mother of movie theater gunman james holmes is pleading for mercy, telling the jury she had no idea her son would carry out one of the worst mass shootings in america. >> i would have been crawling on all fours to get to him. he's never said that he wanted to kill people. >> reporter: family and friends who call the gunman jimmy described his upbringing in california as typical. >> he was happiest when he was playing soccer. >> reporter: his parents, robert and arlene insisting he was never mean-spirited and always took good care of his younger sister chris. >> and do you still love him? >> i still love him. >> reporter: chris holmes visited her brother in jail once and says she almost didn't recognize him. >> his eyes seemed a lot different, and his whole demeanor in general was a little bit different than when i had previously seen him. >> reporter: prosecutors are asking the jury to sentence the shooter to death. the defense is lobbying for life in prison. mental health experts on both sides agree holmes is mentally ill. >> he didn't ask for that. schizophrenia chose him. he didn't choose it. >> reporter: for 59 days they have sat in court just feet from their only son but a world away. tonight finally breaking their silence, the holmes family hoping the jury will spare the life of a convicted mass murderer. jacob rascon, nbc news, los angeles. an 11-term member of congress from philadelphia has now been indicted in an alleged racketeering conspiracy. democratic congressman chuck epetah and four associates are accused of schemes to misuse funds in connection with his unsuccessful 2007 mayoral bid. the congressman denies any wrongdoing. his wife renee chenault fata is an anchor on our philadelphia station. she is not charged but the indictment refers to her as part of an alleged plot to discuss a payment from a lobbyist as a car sale. tom brady's hitting back hard at the nfl and the league commissioner over the decision to uphold his four-game suspension, sidelining one of the league's biggest stars over allegations of cheating. nbc's ron mott with what brady and his team are now saying. >> reporter: day one the patriots training camp and the focus is off the field. today a surprise appearance by team owner robert kraft, reacting to nfl commissioner roger goodell's ruling upholding quarterback tom brady's four-game suspension for his role in the six-month deflategate saga. >> i was wrong to put my faith in the league. >> reporter: brady himself took to social media, defending himself on facebook against nfl claims that he destroyed his cell phone and 10,000 text messages during last season's investigation of deflategate. brady said he turned over pages of cell phone records and all of the e-mails requested and even tried to retrieve text messages while making it clear he would not turn over his phone. "to suggest that i destroyed a phone to avoid giving the nfl information it requested is completely wrong." earlier today lester spoke to brady's agent, done yee. >> he denies any wrongdoing. and if that's the case we're left with the alternative that commissioner goodell is without justification trashing one of the league's biggest superstars. is that what we're left to believe? >> that's what we're left to believe, lester. that's one reasonable inference. as you know it's been well documented in the past two years that this commissioner's decisions on discipline have been quite erratic. >> reporter: patriots coach bill belichick had little to say on the issue, deflecting reporter questions. >> we're going to take it day to day start training camp. it's already been addressed. >> reporter: no home field advantage from one boston sports columnist calling brady and the team cheaters. >> i think that common sense tells you they were up to something here and their continued insistence that they didn't do anything wrong i think is one of the reasons they're in the predicament they're in. >> reporter: deflategate rages on now moving from the court of public opinion to federal court. ron mott nbc news boston. after six days of searching, the coast guard says it is not giving up on the desperate race to find two teens missing off the florida coast. they vanished on friday. their boat was found sunday without a trace of either of them. their families are holding out hope of finding them alive. they describe the boys as experienced on the water. still ahead tonight, an american dentist now in hiding amid intense outrage over the killing of that beloved lion in africa. what he's now saying about what happened. and later, a story you will love. a remarkable young man who made an unusual request of his mailman. what he asked for that prompted an unbelievable response with the pain and swelling of my moderate to severe rheumatoid arthritis... ordinary objects often seemed... intimidating. doing something simple... meant enduring a lot of pain. if ra is changing your view of everyday things orencia may help. orencia works differently by targeting a source of ra early in the inflammation process. for many, orencia provides long-term relief of ra symptoms. it's helped new ra patients and those not helped enough by other treatments. do not take orencia with another biologic medicine for ra due to an increased risk of serious infection. serious side effects can occur including fatal infections. cases of lymphoma and lung cancer have been reported. tell your doctor if you're prone to or have any infection like an open sore, the flu or a history of copd a chronic lung disease. orencia may worsen your copd. if you're not getting the relief you need... ask your doctor about orencia. orencia. see your ra in a different way. ugh! heartburn! no one burns on my watch! try alka-seltzer heartburn reliefchews. they work fast and don't taste chalky. mmm...amazing. i have heartburn. alka-seltzer heartburn reliefchews. enjoy the relief. you do all this research on the perfect car. gas mileage , horse power... torque ratios. three spreadsheets later you finally bring home the one. then smash it into a tree. your insurance company's all too happy to raise your rates. maybe you should've done a little more research on them. for drivers with accident forgiveness liberty mutual won't raise your rates due to your first accident. see car insurance in a whole new light. liberty mutual insurance. heart health's important... ...so you may... take an omega-3 supplement... ...but it's the ingredients inside that really matter for heart health. new bayer pro ultra omega-3 has two times the concentration of epa and dha as the leading omega-3 supplement. new bayer pro ultra omega-3. anger is growing tonight over the american dentist who hunted and killed a lion in africa that turned out to be well known and beloved by tourists. and protected in a wildlife refuge. the outcry has led him to temporarily close his practice and keep out of the public eye. nbc's kevin tibbles has more. >> reporter: cecil's death continues to spark global outrage. and the office of the minneapolis dentist accused of luring the beloved lie frn a zimbabwe game preserve and killing him has become a focal point. >> it's a barbaric hobby. >> killing cecil is not right. >> reporter: walter palmer a lifelong trophy hunter reportedly paid more than $50,000 for the hunt in early july. he claims he paid his guides to obtain proper permits. today in zimbabwe they appeared in court, one charged with poaching. cecil's killing triggered a huge outcry on social media. on late-night television jimmy kimmel became emotional. >> if you want to make this into a positive, you can -- sorry. >> reporter: today palmer sent a letter to his patients saying he has had to close his practice because of all the attention. he repeated that he is willing to cooperate with any investigation. cecil was 13 a tourists' favorite fitted with a tracking collar studied by researchers. >> cecil was a simply magnificent lion. myself and my team have watched him for hours. indeed weeks, months and years. >> reporter: there is now concern for cecil's cubs. without a father to protect them. each year u.s. hunters import some 800 lions as trophies. that's about 2 1/2% of the world's population. outside palmer's dental office today an artist paints a portrait of cecil. he says he hopes to sell it and give the proceeds to a wildlife conservation fund. kevin tibbles, nbc news minneapolis. we're back in a moment with the dangerous heat wave gripping much of the country. al roker is going to join us in just a moment. get fast-acting, long-lasting relief from heartburn with it neutralizes stomach acid and is the only product that forms a protective barrier that helps keep stomach acid in the stomach where it belongs. for fast-acting, long-lasting relief. try gaviscon®. benny's the oldest dog in the shelter. he needed help all day so i adopted him. when my back pain flared up, we both felt it. i tried tylenol but it was 6 pills a day. with aleve it's just two pills, all day. now i'm back! aleve. all day strong. my constipation and belly pain feel like a raging storm. i've tried laxatives but my symptoms keep returning. my constipation feels like a heavy weight that keeps coming back. vo: linzess can help. once-daily linzess treats adults with ibs with constipation or chronic constipation. linzess is thought to help calm pain-sensing nerves and accelerate bowel movements. linzess helps you proactively manage your symptoms. do not give linzess to children under 6, and it should not be given to children 6 to 17. it may harm them. don't take linzess if you have a bowel blockage. get immediate help if you develop unusual or severe stomach pain especially with bloody or black stools. the most common side effect is diarrhea, sometimes severe. if it's severe stop taking linzess and call your doctor right away. other side effects include, gas, stomach-area pain and swelling. bottom line, ask your doctor about linzess today. unbelievable! toenail fungus? seriously? smash it with jublia! jublia is a prescription medicine proven to treat toenail fungus. use jublia as instructed by your doctor. look at the footwork! most common side effects include ingrown toenail, application site redness, itching, swelling burning or stinging, blisters, and pain. smash it! make the call and ask your doctor if jublia is right for you. new larger size now available. iran keeps their nuclear facilities. military sites can go uninspected. restrictions end after 10 years. then iran could build a nuclear weapon in two months. iran has violated 20 international agreements and is the leading state sponsor of terrorism. tonight, much of the country is caught in the grip of a dangerous heat wave taking hold as we've often said it's july we know it is supposed to be hot, but this scorching for this long as we've seen in the past can be a real health hazard. al roker's feeling the heat out on the plaza. what are we looking at here? >> lester, we're talking about dangerous heat literally from coast to coast. we've got a big area of high pressure dome of high pressure that's allowed to move further north because the jet stream is way up to the north. plus you add to the heat the humidity. it limits the amount of evaporation from your skin of the moisture so it feels much hotter. 95 in atlanta. it will feel like 103 tomorrow. 101 in charleston. 95 in new york city. 104 in new orleans. and then you look at this. it's going to last right on into the weekend with temperatures into the low to mid 90s. and guess what. the ridge of high pressure builds out west and so we're going to see record-setting heat where we normally don't see, it the pacific northwest. temperatures in the 90s all week into seattle. triple digits in boise, medford, redding, and portland, lester lester. this is going to go right on into the beginning of next week. so we see no relief coming in sight. dangerous conditions will be existing. >> all right. al roker with some happy friends out there. thanks very much. when we come back, a boy who actually asked for more junk mail and why his request is strik when you do business everywhere, the challenges of keeping everyone working together can quickly become the only thing you think about. that's where at&t can help. at&t has the tools and the network you need to make working as one easier than ever. virtually anywhere. leaving you free to focus on what matters most. ♪ [music] ♪ defiance is in our bones. new citracal pearls. delicious berries and cream. soft, chewable, calcium plus vitamin d. only from citracal. seems like we've hit a road block. that reminds me... anyone have occasional constipation, diarrhea... ...gas, bloating? yes! one phillips' colon health probiotic cap each day helps defend against occasional digestive issues. with three types of good bacteria. live the regular life. phillips'. to folks out there whose diabetic nerve pain... shoots and burns its way into your day, i hear you. to everyone with this pain that makes ordinary tasks extraordinarily painful, i hear you. make sure your doctor hears you too! i hear you because i was there when my dad suffered with diabetic nerve pain. if you have diabetes and burning, shooting pain in your feet or hands, don't suffer in silence! step on up and ask your doctor about diabetic nerve pain. tell 'em cedric sent you. finally tonight, the viral sensation that began with a simple if unusual request. a boy asked his postman for the kind of mail most of us throw away. and the reaction has led to special deliveries from all across the world. with thanks to our station ksl in salt lake city for bringing this one to our attention. here's nbc's rehema ellis. >> reporter: if you've ever questioned whether the digital generation values books -- >> i like using my imagination. >> reporter: -- you need to meet matthew flores from salt lake city. >> it's super fun and it's interesting. plus it gets you smarter. >> reporter: this 12-year-old's passion for reading has suddenly set off a global response. >> that's pretty cool isn't it? >> reporter: it all started last week when matthew met his mailman, ron lynch. >> a young man was standing here reading junk mail. and asked me if i had any extra. >> reporter: matthew wanted something to read because he didn't have any books or bus fare to get to the library. lynch was taken aback. >> at 12 years old he didn't want electronics. he didn't want to sit in front of the tv playing games all day. this kid just wanted to read. >> reporter: so the mailman posted matthew's story on facebook. within days a massive response. "when i get my check i'm going to send him a really good book." "have a couple of good books for him. i'll send them in a couple of days." his simple wish is making headlines all over the world. >> i'm excited to read the harry potter ones. >> reporter: hundreds of books are piling up so quickly matthew plans to share them with other kids hoping they'll be surprised and delighted by the generosity of strangers too. >> it made me feel like there was butterflies in my stomach. i'm just super happy. >> reporter: a chance encounter and a very special delivery. >> more books. >> reporter: opening up a new world of words. rehema ellis, nbc news. >> a reminder a lot of good people out there. that's going to do it for us on this wednesday night. i'm lester holt. for all of us at nbc news thank you for watching. and good night. ben affleck on the attack blasting the outrageous new report claiming he's romancing his nanny. >> now on "extra." ben affleck striking back at "us weekly"'s new cover story. >> why it could blow up into a multimillion dollar battle. >> tom brady's super model wife giselle hiding under a burka going in for secret plastic surgery right as the deflate gate scandal erupts again. bobbi kristina's excould be key to the case. celebrity outrage over the killing of cecil the lion. >> sorry. >> jimmy kimmel in tears, his angry message for the dentist who hunted down africa's most famous lion. new video, bachelor receipt kaitlynn. plus six six pack sex and scandal. an extra sneak peek at the new bachelor in