from nbc news world headquarters in new york this is "nbc nightly news." good evening. it is a war seemingly without end as we were reminded today with word a u.s. drone strike targeting al qaeda militants along the afghanistan/pakistan bo killed two western hostages including an american aid worker the u.s. had spent years trying to free and an italian aid worker. their deaths happened in january but were publicly revealed today by president obama. we also learned today two other americans working with al qaeda were also killed. we have two reports and start with peter alexander at the white house. peter? >> reporter: lester goodevening. the president today sa that he deeply grets the loss of two innocent lives and that he demanded the information be declassified insisting the victims' families deserve to know the truth. in an extraordinary statement, president obama today confessed that the u.s. accidentally killed two hostages including an american that had been trying to free for years. >> as president and as commander in chief, i take full responsibility. >> dr. warren weinstein, an aid worker from maryland was kidnapped by al qaeda in pakistan in 2011 gunmen breaking into his house. the 73-year-old grandfather appealing for help while in captivity two year ago. >> now when i need my government it seems that i have been totally abandoned. and forgotten. >> reporter: today weinstein's wife elaine said she and her family were devastated. while she insisted quote, those who took warren captive three years ago bear ultimate responsibility. she also expressed frustration with elementsf the u.s. government whose assistance during weinstein's captivity she described as inconsistent and disappointing. also killed giovanni lo porto, an italian aid worker kidnapped in 2012. the white house says both men's families will be compensated for their loss. >> i regret what happened. on behalf of the united states government i offer my deepest apologies to the family. >> reporte the men we killed in a drone strike in the rugged mountains of pakistan. while the president didn't specifically order the strike the intended target was high al qaeda leadership who, despite hundreds of hours of surveillance they had no information indicating the two hostages were there. it wasn't until several days ago that the u.s. government confirmed the deaths and the president call the weinsteins yesterday. >> it is a cruel and bitter truth that in the fog of war generally and our fit fight against terror specifically mistakes sometimes deadly mistakes can occur. >> reporter: with the government investign n under way, new questions over the administration's extensive use of drone strikes and the unintended consequences. peter alexander, nbc news the white house. this is richard engel. warren weinstein wasn't the only amer killed in the u.s. drone strikes. there were two others fighting with al qaeda. the voice on this video, experts say, belongs to adam gadden. >> these heroes were not 19 armies from 19 countries but rather were 19 mujahadin. >> reporter: an american notice g a notorious propaganda video of the 9/11 hijackers. born adam pearlman hi grandfather jewish he was raised on a goat farm converting to islam in his teens, attending this mosque and getting into trouble there in the mid-1990s for his increasingly extreme views. gadden traveled to pakistan in 1998 at first hiding his face.t he was identified by u.s. officials and in 2006 became the first american charged with treason since the world war ii era. >> his death, the killing of adam gadden is a big blow to al qaeda's operations specifically in the recruitment of westerners. >> gadden was their most famous american. but this man also killed may have been more dangerous. ahmed farouk rose through the ranks to become their second in command in pakistan. farouk was at the same compound where dr. weinstein and the italian aid worker were held and keeping a fellow american hostage for al qaeda. u.s. officials say the cia didn't know it was killing any of these men, not the hostages nor the al qaeda militants, that they happened to be in compounds linked to al qaeda that were attacked. exposing a key aspect of the administration's drone war. the u.s. doesn't always know who it's killing. lester? >> richard engel tonight, thank you, richard. it's been a sad and stunning fall from grace for the man who led american forces in two wars. retired general david petraeus who once also headed up the cia was sentenced today for two years probation and fined 100 hs$100,000 for sharing classified material with his one-time mistress. he gave a statemt to apologizing for his actions. turning to the race for 2016 hillary clinton under fire tonit as she carries on her campaign amid a slew of negative headlines that raise questions about the dealings of her family's foundation goin back to her time as secretary of state. nbc's andrea mitchell takes a closer look. >> reporter: hillary clinton, the biggest celebrity at a star-studded women's conference in new york tonight. >> hasn't this been -- >> repor cheering stop clinton is trailed by a cascade of stories about whether she did favo as secretary of e for donors to her family charities. chelsea clinton, now the foundation's vice chair, defended their work today. >> what the clinton foundation has said that that we'll be even more transparent. >> reporter: when she took office hillary clinton, pressed by the white house, to a memo voluntarily disclosing foreign contributions. but the upcoming book "clinton cash" obtained by nbc news claims she did not live up to that promise. while she was trying to reset relations with russia the book describes how russia's nuclear agency rosatom gained control of a u.s. uranium company. the author peter schweizer writes shortly after the deal was announced bill clinton was in moscow for a particularly well compensated speech. he was paid $500,000 from another russian entity. and the book claims, however hawkish hillary might have been on other deals, this one sailed through. the russian purchase uranium one was approved. the author asks why the apparent reversal? could it be because shareholders involved in the transactions had transferred approximately $145 million to the clinton foundation or its initiatives? s a pouncing. >> look she's going to have to be held accountable like all of us. >> reporter: but the clinton campaign strongly challenged book today writing hillary clinton was involved in the state department's review of the sale to the russians and that nine agencies were involved. a government ethics expert agrees. >> there's no smoking gun. there's no evidence that she changed a policy based on the donations to the foundation. >> but he and other experts say that the book does establish the clintons did not live up to their promise to disclose all foreign donations. on another front today the house benghazi committee said they'll have her testify in public the week of may 18th about her e-mails and return in june to testify about the benghazi attacks. lester? >> an degree wa mitchell in our washington newsroom thank you. that scare in the r we told you about forced a sky west plane to make an emergency landing in buffalo was apparently more serious than we were originally told. it turns out not one but three passengers passed out and more than a dozen fell ill. that forced the pilot to make a steep but harrowing descent. >> reporter: we now know as many as 14 people on board that united airlines sky west flight from chicago to hartford became ill yesterday. it started with er nurse mary cunningham helping a sick passenger hood passed out. >> she's responding her color was awful. she didn't look good. we got her some oxygen. she was much more alert. >> r soon anot p fainted, then a flight attendant and mary herself became ill. i had to sit down. i was short of breath lightheaded, didn't feel great. >> reporte before thr passengers had passed out all seated in the middle of the plane. many more reported being sick. >> i had a headache. i felt a little dizzy, a little tightness in my chest. >> repor fearing the worst, a cabin pressure problem, the captain descended rapidly from 37,000 feet down to 10,000 and averted to buffalo. s scary. there was a lot of people with their heads down praying. >> reporter: once on the ground everyone recovered, no one went to the hospital. firefighters police and sky west maintenance teams examined the plane but so far have found nothing wrong. the airline says it found no evidence of an oxygen leak or pressurization problem. sickened 14 people and caused 3 to pass out remains a mystery. tonight sky west says that plane is returning to service. tom costello nbc news, washington. >> of delays the senate voted to confirm loretta lynch as attogeneral. the vote was 56-43 with 10 republicans joining all senate democrats in voting yes. lynch will replace eric holder and become the first african-american woman to serve as attorney general. for three days a jury has lived the horror of the boston marathon bombing through the words and vivid descriptions of those who survived it. today in the penalty phase of the trial the prosecution rested its case against dzhokhar tsarnaev offering what it calls proof that tsarnaev knew he was targeting children with his attack. pete williams was back in court. >> reporter: it's one of the searing images from boston a police officer rushing a wounded boy from the danger. just moments before 3-year-old leo woolfenden was in this stroller. that's his father steven at the top of the screen unaware that he's heading toward a bomb. people around him wince as the first bomb goes off a block away. just three seconds left dzhokhar tsarnaev passes right by steven and his son in a stroller. further proof that tsarnaev knew children would be among the victims. in court today woolfenden said as he lay on the street his left leg blown off, he noticed his's d because i know if i would ever see my son again. he turned and saw 8-year-old martin richard next to him clearly near death. his mother repeating, please martin. marc fucarile who lost one leg says doctors are working to save another. three dozen bbs are embedded in his body. as for leo, he suffered a fractured skull and perforated eardrum. defense lawyers begin presenting their witnesses on monday includg some of his relatives, hoping to spare him the death penalty. lester? >> pete thank you. in oklahoma new revelations tonight ab the training of reserve deputy received before he says he mistakenly shot and killed a man. an internal review found kirnconcerns about robert bates going back several year. gabe gutierrez has the details. >> in 2009 the tulsa county sheriff's office launched an internal review into the office's treatment of reserve deputy robert bates finding incomplete field training. colleagues reported when confronted bates, a political supporter and campaign contributor of the sheriffs said anyone who took issue with his actions should talk to sheriff stanley glanz. it concluded that bates had received special treatment. on april 2nd, bates shot and killed eric harris a suspect in an undercover firearms sting operation. bates says he accidentally mistook his gun for his taser. >> i shot him. i'm sorry. >> repor the lawy for eric harris' family are now calling on the sheriff to resign. >> the public's entitled to know the truth. the harris family is entitled to know the truth and they need to be transparent. >> reporter: bates' attorney says he has not seen the report but in a written statement said since 2009 mr. bates has received hundreds of hour hs of training and experience in the field. the sheriff's office acknowledges there was a 2009 internal review but a spokesman says no acti was ever taken. earlier this week sheriff glanz acknowledge that he and bates have been close friends for years but insists that bates was properly trained. given what you know now, should mr. bates have been out there that day? >> yes, he should have been. pleaded not guilty to second degree man slaughter and the ju allowed him to travel to a preplanned vacation in the bahamas. his set for july. gabe gutierrez, nbc news tulsa, oklahoma. still ahead here tonight our nbc news exclusive, dr. oz under fire now firing back at his critics who says he pushes so-called quack treatments on his show. the shy kid from the bronx now selling out stadiums around the world. why millions can't allergies can distract you. so when your symptoms start, doctors recommend taking non-drowsy claritin every day of your allergy season. with claritin, you get powerful, non-drowsy relief 24 hours a day, day after day. which is important because with fewer symptoms to distract you you can focus on the extraordinary things you do every single day. live claritin clear. every day. 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. visit jubliarx.com for savings coupons. why am i so awake? did you know your brain has a wake system... and a sleep system? science suggests when you have insomnia, the neurotransmitters in your wake system may be too strong, which may be preventing you from getting the sleep you need. talk to your doctor about ways to manage your insomnia. >>who... is this?! >>hi, i am heinz new mustard. hi na na na na >>she's just jealous because you have better taste. whatever. >>hey. keep your chin up. for years, heinz ketchup has been with the wrong mustard. well, not anymore. introducing heinz new better tasting yellow mustard. mmm! tonight dr. oz is facing new heat as more doctors come out against him, and now it's doctors from within his own hospital raising questions about some of the health advice he dispenses on his show. tonight, in an exclusive interview, he opens up to nbc's stephanie gosk coming out swinging against his critics. >> you may have seen the headlines -- >> reporter: today on his show dr. oz turned the tables attacking a group of doctors from around the country who last week wrote a letter insisting he be fired from columbia university. some of them have their own conflict of interest issues. >> reporter: but now more criticism. in a "usa to posted online today five medical doctors and three ph.d.s from columbia university write many of us are spending a significant amount of our clinical time debunking ozisms. this unsubstantiated medicine sully the reputation of columbia university. before the editorial was published dr. oz defended the content of his show in an exclusive interview with nbc news. >> the show's purpose is not to talk about medicine. the show's purpose is to talk about the good life what you need to do to live your best. >> reporter: but as a doctor going on a show called "dr. oz" don't people that watch your show expect that kind of advice medical advice? >> it's called "the dr. oz show." we very purposefully in the logo have oz in the middle and doctor up in the upper bar for a reason. i want folks to realize i'm a doctor and i'm coming into their lives to be supportive of them but it's not a medical show. >> rep the argu among your critic is as a doctor you should be promoting things you'd promote in your exam room not your living room? >> i'm very respectful of my critics and i understand why you'd be much more comfortable if everything i said on is everything that a doctor would say in his office but that's not what the show's about. >> r it does not call for oz's resignation, but the authors want a disclaimer on his show stating that the opinions expressed may not be based on evidence and aren't endorsed by columbia university. stephanie gosk nbc news new york. >> we want you to know that dr. oz will appear live tomorrow morning on "today." we're back in a moment with a state of emergency as a sleeping giant . congratulations. you're down with crestor. yes! when diet and exercise aren't enough, adding crestor lowers bad cholesterol up to 55%. crestor is not for people with liver disease or women who are nursing, pregnant, or may become pregnant. tell your doctor all medicines you take. call your doctor if you have muscle pain or weakness, feel unusually tired have loss of appetite, upper belly pain, dark urine or yellowing of skin or eyes. these could be signs of serious side effects. i'm down with crestor! make your move. ask your doctor about crestor. working on my feet all day gave me pain here. in my knees. but now, i step on this machine and get my number which matches my dr. scholl's custom fit orthotic inserts. now i get immediate relief from my foot pain. my knee pain. find a machine at drscholls.com [chorus singings:] ♪ roundup ♪ i'm the protector of my patio. killing weeds where they grow. a barrier forms so weeds can't appear - serious weed prevention up to a year. 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just peachy...literally. ink from chase. so you can. >>who... is this?! >>hi, i am heinz new mustard. hi na na na na >>she's just jealous because you have better taste. whatever. >>hey. keep your chin up. for years, heinz ketchup has been with the wrong mustard. well, not anymore. introducing heinz new better tasting yellow mustard. mmm! finally tonight one on one with a mega star romeo santos is the biggest name in latin music right now. packing stadiums across the world and racking up the kind of video play that would make even the other famous names in music jealous. nbc's katy tur caught up with romeo on tour. ♪ >> reporter: romeo santos isn't just a star. he's a from argentina to new york. where the mill len upcrooner sold out yankee stadium two nights in a row, the first for latin artist. the video for his hit "indecent proposal" has 660 million views. that's more than the most popular beyonce or justin timberlake videos combined. we caught up with him before he took the stage in the netherlands, of all places. >> i like to describe myself more as a humble kid from the bronx that you know is blessed to have so many fans that are so loyal and supportive. >> reporter: born and raised in the bronx by his stay at home mom and construction worker father santos was a shy kid who found his love for singing at 13 in the church choir. from there he started a boy band with his cousin an friend. and by 21 his band aventura made it big. >> listen to bachata. and i always felt like something about that music like wow, i just felt like i was going to bring something new to the table. >> reporter: and he did. taking bachata, a traditional dominican music genre about love and heartacho the masses. today at 33 romeo knows how to play to his fans. especially the women who love him. >> they're all my juliets. >> what the other romeos out there. are you worried about them getting jealous? >> well there's only one. >> reporte one romeo, millions hooked. katy tur, nbc news rotterdam, the netherlands. > we expect the cr to start lining up early here in new york as romeo performs live monday morning on "today." come on down i might see you there. that will do it for this thursday night. i'm lester holt. for all of us at nbc news, thank you for bruce jenner finally confessing his fears revealing his number one question about living life as a woman. >> now, on "extra." bruce jenner on final countdown to his headline-making transformation. >> it's going to be an emotional roller coaster. >> all new bombshells of the diane sawyer tell all and chris jenner on a double date grilled about the interviewly getting some popcorn and watch the show? did bobbi kristina have a death wish? >> do you think it was a suicide attempt? >> booze, drugs, intervention after intervention as bobbi kristina's boyfriend sits in rehab. his brother breaks the family's code of silence. >> shocking new claim about whitney. is this an intervention? >> troubled real housewife kim richards storms out of the therapy session. what happened seconds later. then, we asked trump the billion billion-dollar presidential question. >> the trump white house? sarah jessica parker and tracey on a carrie bradshaw fame. >> tuxed