the question is, could it be the answer for so many americans struggling with their weight? answer for so many americans struggling with their weight? "nightly news" begins now. captions paid for by nbc-universal television good evening. the civil war in syria today reached the inner ring around president assad and we begin tonight with an operation, the likes of which we've seen in the movies, a bomb has killed three members of president assad's national defense team. someone who knew what they were doing, someone with access to the inside snuck an explosive, a big one into the senior structure of syrian security. it is a further indication that we could be in the closing stages of the civil war in syria. we begin our reporting here tonight with our chief foreign correspondent, richard engel. he is just back from syria with us here in the studio. >> picture this inside job. a meeting in damascus this morn

morning of the top officials there to discuss how to continue to crackdown, how to keep the rebels from advancing on damascus, when suddenly, the room explodes. it is just a sign of how little control the government still has, and a sign that this could be one of the final stages in this conflict. government troops fight to retain control of damascus after an attack that has shaken the regime and raised doubts about its survival. buildings in the capital smoldered, in fighting so intense the army had to call in helicopters. this just hours after state television announced that a bomb exploded wednesday morning during a national security meeting killing at least the defense minister, his deputy who was also president assad's feared brother-in-law, and the vice president. more than a dozen others in the meeting were reportedly injured, perhaps killed. it is unclear if president assad was there.

the government isn't saying. >> it is part of the conflict. >> reporter: assad has not been seen publicly since this interview with german television two weeks ago. the opposition says it planted the bomb with inside help. >> the army can reach anyone inside damascus. even bashar assad, himself, he is not safe anymore. >> reporter: after 17 months of fighting, syrian rebels have carved out rural safe havens. brought the fight to damascus and now brought it to assad's inner circle. the defense secretary leon panetta called today's attack a real escalation. >> this is a situation that is rapidly spinning out of control. >> reporter: already in rebel held provinces in syria, they are celebrating hoping today's bombing is a sign that assad's

days in power are numbered, as u.s. officials renew their calls for the syrian president to immediately step down. in addition to disrupting the leadership, you could imagine the psychological impact of an attack like this. bashar al assad doesn't know who he can trust. he doesn't know who has been infiltrated in his inner circle. it is a major turning point. >> very interesting to see what happens next. if he was anywhere near where the explosion went off. richard engel with us in the studio. thanks. to the other front we're covering this evening, somebody today blew up a bus carrying israeli tourists who were traveling overseas and almost instantly, the israelis said it showed the involvement of iran. six people are dead. dozens more hurt and the tension in an entire region just spiked. nbc's martin fletcher with us fromel aviv tonight. martin, good evening. >> brian, good evening. israeli security officials say

that they warned bulgaria of terrorist plans to attack israelis and they even asked for extra security around buses from airports to hotels. clearly today, it was still not enough security. >> reporter: smoke billowed into the sky, marking the scene of carnage in an airport parking lot. 5:30 in the afternoon local time, 150 israeli tourists were boarding buses to go to their hotels in the black sea resort. one bus carried mostly teenagers. an israeli eyewitness who was lightly wounded said a man boarded the bus and then a massive explosion. it still isn't clear if it was a suicide bomber, a device left on the bus? police don't have answers yet, and nobody has claimed responsibility. israel's prime minister benjamin netanyahu immediately said, quote, all signs point to iran. and the defense minister widened the net. >> hamas or any other jihadist

group under the auspices of either iran or other radical muslim groups. >> reporter: he warned israel will identify them and, quote, settle the account. iran and israel have a long running war of words and reportedly deeds. this year alone, israel accused iran of attacking its diplomats in india, thailand and georgia. while iran accuses israel of assassinating five iranian scientists. bulgaria is a popular tourist destination for israelis and tonight, barack said the attack would not change anybody's plans. later president obama condemned what he called today's barbaric attack and he vowed to quote, bring to justice those behind it. >> martin fletcher in tel aviv tonight. martin, thanks. we are joined tonight in our studios by our chief foreign affairs correspondent andrea mitchell. i have to say, the world nine days from now is going to gather in london for the olympic games and the last thing the world

needs is tension in this area involving israel and iran. >> and the tension is only going to escalate. what you heard netanyahu say today is that iran is responsible, most likely responsible, and that the defense minister said that they will settle this account. the president called netanyahu and the clear message is, let us help you with intelligence, with forensics. we will get these guys. don't start a war over this and don't use this as a pretext to attack a nuclear facility. >> let's back up to the other front where we started tonight. syria. are your sources concurring with richard's feeling that this indicates, if they can get in this close, we're in the closing stages. >> this is certainly the hope at the white house. intelligence officials say it could be either way. either it could be that this is an inside game, and now the people around assad also realize that the gig is up and they will start deserting him and he realizes that he has to cut a deal. the other argument could be this minority around assad will say, we're going to go down shooting and fight until the end. it could not be the final end

game. the white house does believe strongly that this is the message and this is by the way, what the president is telling vladimir putin. that was his other big call today. they still have differences, according to the white house, but they're saying you have to now let the u.n. do something. time is running out. >> you've seen plot lines like this play out. andrea mitchell, thank you for being with us tonight. in our post 9/11 era, a report out today will get a lot of attention. it in effect says it is possible to be on the u.s. government's no-fly list and yet still be able to take flight training because of a lack of cross checks and background checks, and our justice correspondent pete williams is in our washington bureau reporting on all of it tonight. pete, did we get it about right? >> yes, and it is a sensitive issue, brian. some of the 9/11 hijackers trained at u.s. flight schools, even though they were here illegally. many more background checks are in place now but government auditors said some foreign students are still allowed to get training without thorough

screening against terror data bases. they said the system should do better at blocking flight training for people here illegally and congress was told the tsa does not do background checks at all for american citizens who want to go to flight school. that means a u.s. citizen on the no-fly list would be banned from being a passenger but could still get training on how to be a pilot even though that person could not get a pilot's license. now tsa says it is barred by law from checking on a u.s. citizen who wants to get flight training. several members of congress are now vowing to close that loophole, brian. >> pete williams reporting on the story tonight from d.c. pete, thanks. wild weather in about the eastern third of our country causing headaches for a lot of air travelers tonight. as cool air pushes out, the latest heat wave stirs up some very violent storms across a wide region. our friend weather channel meteorologist jim cantore is with us from headquarters tonight. jim, some real violent weather across a big area. >> yeah, big time.

a lot of times we focus on tornadoes and hail size and damaging wind threat. today it was all about the lightning. check out this picture that was captured. the empire state building frequently gets struck by lightning. rarely is it caught on camera. it was today. and we just had electrical storms all over the place. the chronology of this thing was, record highs in the hundreds from hartford, connecticut, all the way down to washington, d.c. really by about 2:00. after that, storms just blew up and we're talking about storm that went from ground to 60,000 feet, 12 miles high in about 60 minutes. so real, real big storms. that caused a major logjam from boston all of the way to dulles where we had a complete shutdown of aircraft for about an hour. of course, the results from that are lots of wind damage, and lots of structures that were struck by lightning and unfortunately, well, hot temperatures that will bulge to

the heat. watch this tomorrow. an area that hasn't seen beneficial rain in a month and a half has a chance of it but it comes with a risk of severe storms as well. >> let's hope for the precipitation part of that. jim cantore in headquarters tonight. an update on this drought that is now over half the nation in its grip. the official drought disaster area grew even larger today. eight more states aed to the list and there was more worry today about the prices of so many consumer products as a result. especially corn and all that it goes into. nbc's kevin tibbles is with us from the floor of the chicago mercantile exchange. good evening. >> brian, here at the merc where they trade in the commodities that we have been reporting on, talk again today was of corn. up another percentage point and of course, it is at its highest levels in over a year. meanwhile, the evergrowing list of drought disaster areas stands at more than 1,200 counties. today the secretary of

agriculture said 3/5 of the american land mass has been affected by this lack of rain. and he's called on congress to assist the american farmer. now it is not just corn, because beef, pork and poultry producers have been selling off early, fearing rising feed prices. and as a result, in the short run, vilsack says the meat prices may go down, but by year's end, he expects consumers to be paying more. there's one other thing. consumers should be suspicious of price rises right now being blamed on the drought because he said it will take some time to filter into the economy. so he's asking consumers to actually be vigilant at this time about price gouging. brian? >> all right. thanks for that report from the chicago merc where the prices are often set. kevin tibbles in chicago. still ahead, as we continue along the way, the new diet pill being hailed as possibly the next great hope. is it really, however, the answer so many americans have been waiting for? later, an amazing discovery tonight. three miles down. the sunken treasure many thought was lost for good.

and celebrating the life of one of the most beloved people on the planet. nelson mandela marks a milestone.

for the second time in as many months, the fda has approved a new diet drug. this after more than a dozen years with no new weight loss drugs coming to the market. patients and doctors hope qsymia will help tackle the country's obesity epidemic, but there are still potentially risky side effects. our report tonight from tom costello. >> we grab some apples -- >> reporter: 43-year-old christina elwell works at staying healthy. she eats right, avoids sugar and processed foods, but after her third child, she just couldn't lose the extra weight. until she began taking the same combination of weight loss drugs found in qsymia. she soon dropped 35 pounds. >> for me, it was a magic pill that certainly filled that piece that helped me begin to lose the weight. >> lost about as much as someone

who had surgery. >> reporter: for ten years, obesity specialist has been prescribing a combination of the that now make up qsymia. an appetite suppressant and an anti-seizure drug. but only to severely overweight patients with related medical problems. >> this is not a weight loss medicine to look good in a bathing suit before you go away on vacation. >> reporter: qsymia is the second obesity drug to get fda approval just this summer. two years ago the fda refused to approve it, concerned about increased heart rates and birth defects. >> both of these recent ly approved drugs in our estimation reduce cardiovascular risk which is the last thing you want to do for people who are already at cardiovascular risk because think are overweight. >> reporter: yet with one out of three americans battling obesity, the fda is hoping the rewards of taking qsymia outweigh the risks. it is intended for the american woman who averages 5'4" but

weighs at least 174 pounds and suffers from obesity related diseases. the american man averages 5'9" and is considered obese at 203 pounds. >> these new medications bring our patients some hope. that we will finally have a medication that we can use as another tool that we can bring to bear on weight loss. >> reporter: hope for patients like christina, looking for a powerful ally in the war on obesity. tom costello, nbc news, washington. we are back in a moment with a former president as we've never heard one before.

we want to show you some surprising comments from former president george w. bush. he doesn't give many interviews and in an interview with the hoover institute, he says why. he said he wants to fade from public view and public life as much as it is possible for any former president. >> but i really don't want to be in the public eye anymore.

and i feel a certain sense of liberation not being out there. >> you like it better. >> i really do. eight years was awesome. and i was famous and i was powerful, but i have no desire for fame and power anymore. >> the former president said part of his motivation in wanting to fade from the scene is not to be seen trying to interfere in any way the current president. a warming atlantic ocean has taken its toll again on one of greenland's giant glaciers. a piece twice the size of the island of manhattan has broken free. scientists have been watching a crack in the glacier for years. nasa took a satellite photo as it started to break off days ago. two years ago a piece twice the size of this one broke off. scientists will be watching carefully again to see if this is the end of it for now. this next item will get the attention of a lot of folks in our country. a new analysis shows for the first time, canadians have a higher average net worth than

americans. $363,000 for canadians to $319,000 for americans. one big factor in canada's favor, home prices held up there better after the financial meltdown here. a huge find three miles beneath the surface of the ocean in the north atlantic. 48 tons of silver bars found in the wreck of a british ship that was taken down by a german u-boat in world war ii back in february of '41. the haul estimated to be worth a starting price of $38 million. and only about 20% of the treasure lying inside the ship elsewhere is scattered. experts say it could be the largest precious metal recovery ever. the folks at the zoo in houston, texas, have sent out this photo of a precocious monkey they say might be in on the joke. they grabbed this photo off a camera set up to secretly record wildlife in borneo, but it

certainly appears the monkey seems to know exactly what is going on here. one twitter user speculated, it was posting for a new profile photo on match.com. when we come back here tonight, our report from south africa as nelson mandela marks a big birthday.

♪ happy birthday to you ♪ happy birthday to you >> a joyful day in johannesburg. across south africa for that matter including this group of children. a small part of the estimated 12 million kids who were organized to sing happy birthday to nelson mandela. one of the towering figures of our modern world turned 94 today. yesterday he met with former president bill clinton who said mandela appeared to be in good spirits, was looking well though he is frail these days and unable to walk. it is another milestone for a man who remains a powerful influence over his country. especially the young people there. many of them now thriving, thanks to the freedom he fought so hard to win. our report tonight from nbc's ron allen. >> reporter: they're called the born-free generation.

south africans, 18 or younger. born since the historic 1994 elections that made nelson mandela president and put south africa on a new path after decades of apartheid. you all know mandela. what do you think of him? >> i think if it wasn't for him, a lot of us would my grandmother didn't have a chance to go to school. not be here. she doesn't know how to write. >> reporter: this year as the born free become adults, they're thinking more about mandela's dream of a rainbow nation with opportunity for all really exists. >> as much as things have changed, a lot of things haven't changed. >> there is still a lot of racial tension between people. >> i'm more optimistic. >> reporter: they attend one of the country's most respected universities. under apartheid, he would have been classified as black. alex, mixed race. michael, white. >> reporter: what is it like being a white south african these days? >> it has a few challenges.

>> reporter: challenges like black affirmative action programs that can limit opportunities for whites. some 20 years later, south africa is a complicated society where race still determines a lot about who gets what and how people live and work. for the most part, black south africans control the country's government and politics while white south africans control the country's business and wealth. it is a divide that is strikingly visible with suburban neighborhoods and shopping malls almost exclusively white. while the majority of blacks still live in the poor parts of town. decent housing, good schools and jobs are rare. but at this museum, once a notorious political prison, many of these students said they believe history won't hold them back. >> the world is my stage. i can express myself the way i want to and i have no limits. >> reporter: for generations, hoping the promise of

opportunity and justice now enshrined here burn even more brightly for them. ron allen, nbc news, johannesburg. >> that is our broadcast on this wednesday night. thank you for being here with us. i'm brian williams. we hope to see you right back here tomorrow evening. we hope to see you right back here tomorrow evening. good night. -- captions by vitac -- www.vitac.com good evening and thank you for joining us. >> what must have been a horrifying sight. a stroller crushed in an intersection injuring a mother and her 1-year-old child. that accident unfolding this morning in fremont. nbc bay area's arturo santiago joins us with details.

this actually started because of road rage? >> reporter: it started about 11:00 this morning. two cars were involved in some kind of altercation, they started racing each other. it got a little bit too crazy for one p of those drivers so he backed off. the other car ended up hitting a mother and her two children. the mother was at the police department just hours after the incident. she had a 1-year-old daughter in a stroller that was hurt, but her injuries are not serious. now the family of three was crossing the street and at the same time that road rage car was still speeding down peralta, he lost control while turning northbound on to free mochmont t the 43-year-old mother and her daughter. the man is a 23-year-old man from union