Interview that comes at a critical time for an entire region of the world. Nbcs ann curry has made her way to iran where she has been the First Western journalist to interview the new president of iran. This will be the first time millions of americans get to see and hear him. And that includes many in the obama administration. What youre about to hear is significant because it represents the first reason for any optimism, the first sign of any movement from iran on the issue of Nuclear Weapons, right when the crisis in nearby syria has reached its peak. So we begin with ann curry in tehran. Reporter good evening. In our interview, he was scleerl sending a message that under his administration, there is a different iran, one that wants to make a deal. The world believes that iran could build a bomb very quickly. Youve said this period of time for resolving the Nuclear Issue will not be unlimited. Just how short is this window . Weeks . Months . Or years . Translator we have never pursued or sought a nuclear bomb, and we are not going to do so. We are solely seeking nuclear technology. Reporter can you say that iran will not build a Nuclear Weapon under any circumstances whatsoever . Translator the answer to this question is quite obvious. We have time and again said that under no circumstances would we seek any weapons of mass destruction, including Nuclear Weapon, nor will we ever. Reporter the Supreme Leader made a very strong statement just recently on diplomatic flexibility. He said i believe in whats already been called heroic flexibility, even a wrestler can show flexibility. What does that mean to you, mr. President . And what does it allow you in your negotiations on the Nuclear Issue . Translator in this nuclear program, this government enters with full power and has complete authority. I have given the Nuclear Negotiations portfolio to the foreign ministry. The problem wont be from our side. We have sufficient political latitude to solve this problem. Reporter on syria, he sa said iran played a major role in krafting the deal. Reporter can you be sure assad will give up all his chemical weapons . Translator we are not the syrian government. We are one of the countries that seeks peace and stability and the elimination of chemical weapons from the entire region. Reporter do you believe the United States president obama looked weak in backing off an air strike on syria . Translator we consider war a weakness. Any government that decides on war we consider a weakness, and any government that decides on peace, we look on it with respect for peace. Reporter and the president confirmed that he exchanged letters with president obama recently, calling them teeny steps for an important future. He hasnt ruled out a meeting with president obama. All right. Ann curry by satellite. Much more of anns reporting on our website and tomorrow morning on today. For more on this we want to go to Andrea Mitchell at the state department. So this is the newman. The world came to know ahmadinejad before him. What was important about what he just said versus what we he have heard from iran before . Reporter well, this is a very, very big deal. And i can tell you at the white house and the highest levels of the state department, they were watching for this all day. They were looking for these signals in this interview. He made it very clear he wants a deal on the Nuclear Weapons. The president said just yesterday he wants to test his seriousness. And that is what theyre going to be looking for at the u. N. Theres no formal meeting scheduled. Theyre not planning one, but unlike his predecessor, you can very well understand that when both of them are at the u. N. , same time, same place, theyre going to look for an opportunity to see each other, perhaps to have a real conversation. And they believe iran wants this because of the sanctions, because theyre crippling the economy, that the time is right, that there is a very short window to see whether iran is serious, whether this man with a clerical background can do the deal. I was told that they have been working on this back channel for two years, and one of the Significant Players is the foreign minister who is wellknown to everyone in this administration. Thank you both. We turn from tonights news on Foreign Affairs to the shooting rampage at the Washington Navy yard and the acknowledgement today by the u. S. Secretary of defense, there were many red flags that were missed about the past behavior of this gunman aaron alexis, as the gunmans mother broke her silence. From our dc newsroom, we have the latest. Reporter more signs tonight of the troubled mind of aaron alexis. He scratched two phrases into the shotgun, quote, better off this way and my elf weapon, we cant explain. . How could aaron alexis get and keep a security clearance allowing entrance into the navy yard after run ins with the police and psychiatric problems. There were problems, of course there were. Should we have picked them up . Why didnt we . All those need to be answered. Reporter after interviewing survivors, officials give this revised account of what happened inside. Alexis entered building 197 carrying a shotgun in a bag and went directly into the fourth floor ducking into a mens room came out firing and reloading. Virtually all those kill wrd hit with shotgun blasts. He then dashed back to the entrance, shot a security guard, took his handgun, raced back upstairs and continued shooting until killed by police. Investigators say they have no idea why alexis selected that building. Theyve identified no specific target of his anger. Alexiss mother says she has no answers either. I dont know why he did what he did. And ill never be able to ask him why. Aaron is now in a place where he can no longer do harm to anyone, and for that, i am grad. Reporter as the government looks at how to factor Mental Health issues into background investigations, the top general sounded a note of caution. That men and women should have the opportunity to overcome their mental disorders or their mental challenges or Clinical Health challenges and shouldnt be stigmatized. Reporter nbc got a look inside the Trauma Center where survivors were brought monday. We talked to doctors who treated the wounded. The patients that are still here are in good condition. Theyre recovering well, and we expect them to make an excellent recovery. Reporter we know that alexis told the Newport Police last month that he was hearing voices. Now the va says he said he was only having trouble sleeping. They did tell the navy what happened. The navy says that was never reported any further of the chain of command. Thanks. The Economic News today sent the stock market soaring, but it wasnt necessarily good news for everybody and the rest of the country. The long and short of it is this the American Economy is not doing well enough to be left alone. After saying it was gaining strength, the head of the Federal Reserve decided to keep going with economic stimulus to try to encourage job and economic growth. Both the dow and the nasdaq closed at record highs. Mortgage rates are expected to drop, but the fed believes the American Economy still needs a continuing infusion of 85 million a month. And there are growing concerns that a potential government shut down in washington will do even more damage. Now across the border. Near ottawa today, a terrible crash between a passenger train and a doubledecker bus. Survivors on the bus said many passengers were screaming at the driver to stop just sends before the bus crashed through a crossing barrier into the train. Part of the via system in canada. Its an increasingly desperate situation in and around the resort city of acapulco. Hit hard by Tropical Storm manuel which flooded the city and some resorts and the heir port. The death toll is now listed at least 80. Most of the tourists are trapped with no power, no access to cash and no way to get home. Back in this country, in colorado, the history making floodwaters there have started to recede, revealing the full scope of the devastation beneath and the cleanup now begins. For tens of thousands of families. At the same time remember almost 2,000 people are still listed as missing. Including a wife who sadly never came home. We have that story tonight from boelder. Reporter the siblings have been together waiting for the past week. Their parents lived in hard hit lions. He came up saying you need to evacuate immediately. Reporter they left in separate vehicles and when sharon saw flooded roads, she pulled over. Instead, jerry headed to a shelter at the Elementary School where he taught sixth grade. Bonnie newman was there. I saw jerry there. And i said wheres sharon . He says im looking for her. Have you seen her . Reporter jerry left sometime after that and hasnt been seen since. He was safe. Why did he leave . I think he wanted to see if i went home. I think its a love story. Theyre both so brave. Theyre so brave. Reporter they had to get to each other. They looked for each other. Reporter you went back looking for him . I started to, but then i had to be rescued at the other end of town. Reporter when her car flooded, rescuers sent the only vehicle that could get through. They put a life jacket on me and sat me on the seat and away we went. Reporter we saw the footage a million times on thursday and had no idea it was our mom. Reporter in a Small Community like lyons, Everybody Knows the long time football coach and teacher, and everyone seems to be searching. I had all my brothers, cousins, aunts and uncles. Reporter and that is what his family is celebrating now. Everybody thats ever been in school has been out looking for him. And i thank everybody so much. We are just swollen with pride for him. I cant say enough about how proud i am to be his daughter and how proud i am that he did all the right things in the end. Reporter today jerrys soninlaw and grand son were able to get behind this roadblock here and up into the canyon to look for any more clues. So far the only thing theyve found is his overturned pickup truck in the river down from his house. They know thats not a good sign, but they are still clinging to hope. What a desperate story going on so many days now. And we grieve for these families that have suffered the ultimate loss. Still ahead tonight, after a break, we will take on a consumer news story. Its about those expiration dates on just about everything. What you should know about them so you dont throw out more than you should. And later, the police in washington found themselves in the center of the news this week and what this does to how she sees her job. Were back. And as we mentioned, we have a consumer story that should be helpful. Its about what we buy, what we consume, and what we throw away, believing its gone bad, no longer good. Its about the sometimes vast difference between the selby date on a product and the use by date. And when something really does go bad and how it all ties into staggering waste in this country, often because of consumer misunderstanding. Our report tonight. Reporter americans are wasting food, a lot of it, 160 billion pounds a year, about 40 of the food supply. That means an average family of four spends more than 1500 a year on food they never eat. A report released today blames, in large part, a confusing and unregulated labeling system. Food is actually still good after the sale by date and often still safe well after the use by date. These eggs have a use by date of october 16th. And typically eggs are good a few weeks beyond that date. The question is, would anyone really consider eating them then. You open the refrigerator in november. Do you make an omelet . No. I probably would not. Reporter we got shopping tips. You absolutely can eat something after the selby date. Sometimes it will say use or freeze by. And i think thats really useful information for consumers. Reporter enjoy by september 21st. What does that mean . This product is going to be at its peak quality on this date. Youre not going to get sick on the 22nd. Typically this will get slimy like lettuce does before it will make you sick. Reporter can i drink this . Depending on how you handle this, if you left it in a hot car for 24 hours, i might not want to drink that. Reporter its about refrigeration. Exactly. Reporter they want the federal government to regulate food labels. Use common sense. If it looks good and smells good, dont toss it. And up next for us tonight, the Community Haunted for decades by a mystery. Tonight it may be solved after the discovery in the waters of a rural lake. [ maragno ] if the car was invented today, it would run on the most Affordable Energy source available. It would charge overnight. Every morning, youd wake up with a full tank, ready to go. If the car was invented today, it would be the 100 electric nissan leaf. With over 200 million gasfree miles driven and automatic hov lane access, the question isnt why electric . Its why gas . [ male announcer ] the 100 electric nissan leaf. Nissan. Innovation that excites. Now get a 2013 nissan leaf for 199 a month. The newest pictures are just in to us from italy showing the Costa Concordia cruise ship upright again after an almost two yearlong salvage operation. The dark side of the ship submerged for so long gives you some idea of the crushing rocks below. Shredded balconies, half submerged staterooms. Back in oklahoma. A whole lot of neighbors and families have been wondering on and off for decades how it is their loved ones, daughter, sons and brothers could have vanished without a trace. Tonight there finally may be some answers due to some old cars pulled from a lake after decades. Reporter Highway Patrol officers were training, using Sonar Technology on foss lake when they made a startling discovery. Caked in mud was a teen dream, a 1969 camaro, near by, a collectible 52 chevy sitting nearly side by side. They were probably stolen vehicles, and we were going to hook onto them and get them out of here. Reporter they turned out to be a watery tomb for six people, three in each vehicle. This woman believes her grandfather may have been in the chevy. I can remember my dad getting in the car, taking my mom, and they would look and look and look. Any trace. Reporter the camaro may be this one. He and two friends were last seen in it the fall of 1970, its believed they may have headed to the lake. The trio vannicishished that ni. The medical examiner cautions it could take months if not years to identify. Now we can close that chapter if our lives. Reporter an unexpected find in an Oklahoma Lake may reopen missing persons cases long grown cold. Nbc news, foss lake, oklahoma. And when we come back tonight, dcs top cop in one of the most difficult weeks ever, and how she says shes able to make a difference in a tough job. The nation went through tragedy this week, and a woman in a big invisible job in washington was tested on the job as we all watched. She is the police chief in the nations capital. Shes cathy la near. And she went into force after that shooting at the Washington Navy yard. Today she sat down with nbc to talk about it. Reporter shes washingtons police chief, these are long days, trying to put her city back together. Reporter have you had time to stand back and reflect on the enormity of this . Yes. Last night late in the evening i think is when it really started to dawn on me, you know, you start thinking about the 12 people who went to work and didnt come home. Reporter she was in her car when the call came in. She was on scene within minutes. Many of these victims are husbands and wives, mothers and fathers. How do you even begin to console a family . I think thats a really important part of our job that sometimes gets overlooked. How do you do it . You say im sorry. Im sorry for your loss. Reporter what kind of perspective do you bring to a job like this . I think women and men do things differently. Some things we dont. Reporter differences that were on full display in the chaos as the chief comforted a fellow officer. He walked over to me and said i was in the building. I was one of the first teams in. And i could see on his face how emotional it was for him, and how he felt, and so my first instinct was to put my arms around him and give him a hug and tell him you did what you had to do and youre okay. Reporter compassion this city needs right now. Nbc news, washington. And that is our broadcast on a wednesday night. Thank you for being with us. We hope to see nbc bay area news begins with breaking news. Our breaking news is in a gated community of san ramon, the s. W. A. T. Team and crisis negotiators are on site of a foreclosed home. In the last 15 minutes, one person has been taken into the man inside÷ did not want to lead. A clash unfolding. A homeowner apparently reportedly, according to police fired shots at the ;rnlocksmit after an eviction fight took a nasty turn. This is in san ramon off the bullinger canyon exit. The house on ashburn circle. That house has been in foreclosure since september of 2010. n we have the latest op the standoff. What are we hearing that the point . We know that someone has been taken into custody. We have not confirmed that have, in fact, it is a suspect. They told us more about this suspect, only that hes 42 years old. Of him by the phone own and off in t 5 afternoon. Take a look at pictures we had inside the estate where is the standoff has been going on for four years now. Theat sheriffs deputivkg are saying they, sq to serve an eviction notice on these very expensive, very large homes. Kq they knocked on the home,i sn nb