hope to see you then. on the broadcast tonight, we are covering two major stories this evening. there's been another mass shooting, this time at a navy facility in washington a short distance from the u.s. capitol. >> it was pop, pop, pop, pop. we just started running. >> more than a dozen people are dead tonight including the gunman. questions remain about whether or not he acted alone. also this evening, the state of emergcy in the state of colorado. >> more than 150 miles of roadway have been washed off the map. >> a growing disaster zone. thousands of homes destroyed. a huge number of missing. a massive air rescue under way and door-to-door searches on the ground. tonight, entire towns are cut off. special coverage tonight on both fronts as "nbc nightly news" begins now.

good evening. there has been another mass shooting in this country. this time close to the center of our government in washington, d.c., not far from the u.s. capitol. gunfire erupted this morning inside the washington navy yard, a complex of buildings dating back to the late 1700s. tonight, at least 12 people are dead. the police say another dozen are injured. seven minutes after the first call to 911, the first police officers rushed in. there were numerous gun battles, apparently, inside one of the buildings before the gunman could be taken down. he has been identified as aaron alexis, a military contractor and former naval reservist from texas. now this ranks with the shootings in ft. hood, texas, and aurora, colorado, in terms of size, scale and death toll. the shooting brought much of d.c. to a stand still. flights grounded, schools locked down. even the u.s. senate locked down

because the u.s. capitol is just a mile and a half away from the navy yard and building 197 where the violence and confusion all started. we have it covered tonight beginning with our pentagon correspondent jim miklaszewski. >> reporter: morning rush hour in the nation's capital pierced by the wail of sirens. 8:15, the first reports that a gunman was on a shooting rampage inside the sea systems command at the navy yard, crackling across fire dispatch radios. >> we have a report on the fourth floor of a male with a shotgun. multiple shots fired, multiple people down. >> reporter: patricia ward was in line at the navy command cafeteria when suddenly the first gun shots rang out. >> there were three gunshots straight in a row. pop, pop, pop. three seconds later it was pop, pop, pop, pop, pop. so it was about a total of seven gunshots. we just started running. >> reporter: for sean carroll it was surreal.

he couldn't believe what he was hearing. >> i was running and i heard gunshots. holy cow. i don't know. they could have been way above me. i wasn't stopping to think what was going on. >> reporter: eyewitnesses report the shooter took up a position on the fourth floor overlooking a massive atrium in the center of the building. from there he reportedly opened fire with an automatic rifle on the breakfast crowd in the food court on the ground floor and others in a third floor balcony area. witnesses also report that the gunman confronted a man in the fourth floor corridor and shot him at point blank range. most of the victims never saw their attacker. a man walking next to navy commander tim juris was cut down by gunfire. >> basically saying that, hey, there is a shooter in your building. i heard two more shots. one of them hit him. he went down right in front of h me. he was shot in the head. didn't look like he made it. i ran from there. >> reporter: 12 people were killed in the shooting spree, several injured the including a police officer. the gunman identified as a

former navy reservist, aaron alexis, was killed in a shootout with authorities who stormed the building. >> the response by uniformed police officers was absolutely nothing short of heroic. >> reporter: the chaos paralyzed the city. nearby schools were locked down, highways shut down. the capitol closed and the nationals baseball game postponed. air traffic from nearby national airport suspended while medevac helicopters air lifted the wounded to a hospital. as the navy yard employees streamed out of the complex, many colleagues were helping each other to safety. at the white house today, president obama paid tribute to the fallen. >> they are patriots. they know the dangers of serving abroad, but today they faced the unimaginable violence they wouldn't have expected here at home. >> reporter: tonight, security is still tight at the navy center which is a couple of blocks behind me.

most of those who work there have to pass through very tight, several layers of security every day and couldn't feel safer until today. and for a military that has grown accustomed to mourning the dead, this incident, brian, has come as a real shocker. >> jim, thanks. jim miklaszewski starting our coverage from washington tonight. now let's get the latest on this investigation. what we know about this gunman. our justice correspondent pete williams has been reporting the story all day. he's in our d.c. newsroom for us tonight. pete, good evening. >> reporter: in the chaos after the shooting was reported police initially thought that more than one gunman might have been responsible. tonight they say they believe shots were fired by one man who apparently had a grudge against the navy. >> we have an active shooter on the fourth floor. i will get you an update on the building location. several victims now. >> reporter: surveillance video captured around the time of the shooting appeared to show three

people with guns drawn prompting an all out search for possible accomplices. >> right now we have multiple pieces of information that would suggest we have at least two other individuals seen with firearms. >> reporter: late in the day investigators believe the shots were fired by one person acting alone who was killed by responding police. authorities say the suspect, aaron alexis, age 34, moved to the washington area four months ago from ft. worth, texas. a navy petty officer specializing in electronics, he served as a naval reservist. he had a job working here as a civilian contractor, but investigators are looking into claims that he recently lost that position which they say may have set him off. the fbi is asking for public help in learning more about what his motive may have been. >> no piece of information is too small. we are looking to learn everything we can about his recent movements, his contacts and his associates. >> reporter: federal officials say they believe he arrived

carrying a shotgun and apparently picked up and then used other weapons from law enforcement officers he shot. >> we heard very close to us a gun blast. and actually we saw bullet holes in the wall above us. >> reporter: officials say he may have entered the building today using someone else's i.d. badge. that badge owner was questioned but officials say tonight they do not believe he had anything to do with the shooting. the owner of this thai restaurant in fort worth said he was the roommate and best friend of alexis. >> we lived together. we shared a house. we'd go out and party. we'd do a lot of stuff together. >> reporter: friends and government officials say alexis worked as a computer consultant at the naval air station in fort worth before coming to washington. a fort worth police report said he was arrested three years ago for firing a bullet at his apartment building that went into the unit above him. he claimed it was an accident while cleaning his gun, but he was later evicted.

friends in texas describe him as a peaceful practicing buddhist. police in seattle, washington, say they arrested him nine years ago after he shot out the tires of a car used by some workers who parked near his house. a police report said he did it during what he told them was a blacko fuelled by anger. brian? >> learning more by the hour. pete williams with the latest on the investigation for us from washington tonight. pete, thanks. tonight the president has ordered flags throughout the district of columbia be flown at half staff. throughout the morning, the number of casualties grew to a startling number. they were taken by air and ambulance to several d.c. area emergency rooms and trauma centers. nbc's tom costello is outside one of them. tom, good evening. >> reporter: hi, brian. we are at washington hospital center. three victims were brought here. they operated on two -- a woman with a shoulder wound and a police officer who had serious leg wounds. they were worried about saving his legs. there is a remarkable story

about a woman shot in the head but the bullet didn't penetrate her skull. no surgery. she is expected to recover. the chief medical officer had thoughts about today's incident and gun violence in general. >> there is something evil in our society that we as americans have to work to try and eradicate. there is something wrong here when we have these multiple shootings, multiple injuries, there is something wrong. i would like you to put my trauma center out of business. >> reporter: we are reminded of recent mass shootings. 26 dead last year at sandy hook elementary. six at a sikh temple in wisconsin. 12 in aurora. 6 in tucson. 13 at fort hood. 32 killed at virginia tech. now 12 here in washington, brian. >> tom costello rounding out our coverage tonight in washington, d.c. tom, thanks.

now to the other front we are covering tonight and have been for days on end. we shift our coverage to boulder, colorado, where today they officially set the all-time record for rainfall. it has resulted in a desperate situation there, as you know. the latest numbers from there are grim. seven people confirmed or presumed dead. at least 19,000 homes destroyed or damaged to say nothing of the estimated 30 bridges that are out. most urgently, hundreds of people are still officially unaccounted for. in a moment, an extraordinary view of it all from just above the unfolding situation. but first the very latest from the ground against this fight against water in boulder, colorado. our national correspondent kate snow is there for us tonight. kate, good evening. >> reporter: good evening, brian. it is believed to be the most massive aerial search and rescue effort since hurricane katrina. all afternoon helicopters ferried people out of neighborhoods and towns completely shut off from the outside world. there are still more people

waiting. >> we have a long ways to go, folks. >> reporter: before dawn this morning dozens of agencies coordinated rescue plans, hoping the rain that pounded boulder overnight and all day sunday would finally let up. >> the helicopters are ready. >> reporter: by mid-morning, a break. battalion leader lieutenant colonel tyler smith suited up and took off in search of the most vulnerable. >> once you cross into the mountains you can see the water flow. many roads are washed out. people are stranded geographically. >> reporter: stranded until today. our cameras were on board for the rescue. children with backpacks, families with pets, people in wheelchairs and walkers, all back on high ground. they have been told to write s.o.s. messages on the driveways, use sheets or flags, anything to draw a chopper's attention. >> anything you can do to get our attention, we'll stop. >> reporter: the roads are treacherous and only go so far. we headed up left-hand canyon in military vehicles with a search and rescue squad out of utah.

do you know if there are a lot of people in there or you have no idea? >> we don't know. my understanding is it's an area that hasn't been looked at yet. >> reporter: the teams find homeowners who want to stay put. >> they are recommending evacuation. there obviously won't be any services available to you for -- they don't know how long. >> reporter: five days in there are entire towns cut off. for the first time we are seeing what life is like in jamestown. >> the creek kept rising. it started taking out houses. we watched one by one houses just cracking off and going into the creek. >> reporter: at boulder's command center they are reaching some people using ham radio. >> everything okay? water, whatever? >> we have no way of refilling the tanks. once the water runs out, it's going to get bad. >> reporter: trying to make contact with the missing, one person at a time. mike horn thought his wife of 38 years, florence, was missing. water rushed through and rolled their house into the river. they were separated. a rescuer found him hanging from a tree.

>> he said, where's your wife. i said, i think she's lost. >> reporter: but she survived, rescued by a good samaritan. >> the most brave man in the world to jump in that water. >> reporter: the good news tonight is as people are connecting with rescuers, connecting with law enforcement, they are finding out those people are accounted for. the number of unaccounted is going down. the bad news, the governor thinks the death toll will rise here. brian, tonight there is still a flash flood watch in effect for parts of colorado. brian? >> kate snow starting off our coverage from colorado. kate, thanks. as you saw very briefly there we found the view from the air is the only real way to explain the dimension of this natural disaster that's being felt over more than a hundred miles in and around boulder. we get the perspective from above tonight from nbc's miguel almaguer. >> reporter: wow, look at this. rockslides, mudslides, so many disasters, so much devastation.

we have seen so many properties impacted. there are simply too many damaged homes to count. >> unbelievable. >> reporter: this is the big thompson river that weaves through a residential neighborhood. it completely wiped out this section of town. the state says at least 30 highway bridges are completely destroyed. more than a dozen dams have been compromised. this one is completely breached. down the road here, these homes are now in jeopardy. >> wow. wow. >> reporter: so many of these smaller communities are completely surrounded by water. no way in or out by foot or by car. there is a chinook helicopter, one of about 15 that have been doing air operations. they are ferrying out thousands of people that are surrounded by water.

we have come along groups of people like this throughout our time up in the air. the national guard has made it clear they want everyone out of this area, but some just refuse to leave. when you see where the cars are scattered and where the homes are submerged, you can tell here that those that were in the path of the water had little or no time to escape. the more we fly, the more land we cover, the more heartbreak we see. >> incredible. >> reporter: above the flood zone, miguel almaguer, nbc news, boulder, colorado. we will take now our first break. still ahead for us tonight, the herculean engineering effort now under way tonight to right the ship. the "costa concordia," the crippled vessel that remains a partially submerged tomb.

back now with the effort underway off the coast of italy. we have a live picture of the shipwrecked "costa concordia."

it's still there right where it slammed into a reef over a year and a half ago, capsizing, leaving 32 dead. now engineers are trying to get it righted and get it out of there. our report tonight from nbc's michelle kosinski. >> reporter: the movement is virtually imperceptible, even in time lapse. ten feet an hour. but the significance here is enormous. this is actually working, engineers say, exactly as planned, down to the millimeter. and the internal structure is staying intact? >> yeah. this is also a reason of satisfaction for us because the vessel is rotating in a uniform way as a solid body. and so this is good news for the future. >> reporter: revealing the blue and yellow tiles of the swimming pool, the glass domed atrium where the movie theater once oneself was. nothing on this scale has ever

been done before. through the night the concordia will be rolled up right. more boxes attached to the side that was on the reef so it can float. there was an hour-long halt this afternoon when a few slack end s of the cables pulling the wreck got in the way of others. trained climbers boarded to move them away. for survivors like luciano costro whose lifeboat barely made it down the ship, the steeply sloping ship. getting rid of the stupidity as he calls it, is a relief. many feel for the victims including a ship's waiter who helped passenger s escape, giving away his own life jacket. >> i hope they find something to give him a decent burial. that's what me, my family, his wife and all of us are hoping for. >> reporter: high hopes on this tiny island. michelle kosinski, nbc news, isa del giglio, italy. when we come back tonight, a recovery update from the jersey

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the u.n. report is out. weapons inspectors found, quote, clear and convincing evidence of large scale chemical weapons use in syria. the report indicates rockets used and the type of nerve gas could only have come from the assad regime. the u.s. and its allies now hoping to force assad's hand. we have an update on where we were for friday evening's broadcast. the seaside boardwalk on the jersey shore. government aid has been made available to the 30 burned-out businesses. while the surviving boardwalk was up and running this weekend and while the investigation into the cause of the fire continues, those who plan to stay and rebuild want to be open by next summer having struggled to open this summer after sandy decimated the area. the white house announced today former army captain william swinson will receive the medal of honor for combat actions while training afghan troops. the army ranger will become the sixth living recipient from our recent wars.

the white house ceremony is october 15th. up next for us tonight, making a difference in the midst of a disaster in the rocky mountains.

tonight our "making a difference" report comes from the flood zone in colorado.

it's about the people who put their lives on hold to help those whose lives have been torn apart by this unstoppable water. nbc's joe fryer has the story. >> reporter: the worst enemy for a restaurant on wheels just might be a flooded street. >> i have lived here my whole life. i have never seen anything like this. >> reporter: the rollin/greens food truck couldn't roll through much of boulder last week. rain dried up all of chef ryan cunningham's business. yet he hasn't stopped rolling. he's giving away food for free. >> i decided, i love cheffing. that's what i do every day. might as well just continue to chef. people are in need, instead of making money. >> reporter: for the past few days cunningham and his fiancee have driven the truck wherever nature allows. >> all right. we have beet salad. >> reporter: delivering food to flood victims like suzanne duvall. >> we just love you. >> reporter: she's already overwhelmed by fellow teachers and neighbors who devoted their day to cleaning out her flooded home.

it's the closest suzanne has been to tears. >> mostly tears of, wow, i can't believe people are helping us. they're so gracious. >> reporter: cheryl trunko has reason to help. hurricane sandy hit her home in new jersey last year. >> i had a bunch of people come in and help my flooded house. i wasn't able to help out. i figured i would pay it forward a little bit and help out today. >> reporter: this is good karma in action. >> we make food. we're trying to do what we do for people who need it now. >> reporter: and those receiving the help won't forget. >> we could not do this without help. >> reporter: that's what it takes to keep a community rolling. joe fryer, nbc news, boulder, colorado. >> because so many of you asked us how to help the victims and families in colorado, we put that information on our website tonight. nbcnightlynews.com. that is our broadcast for this monday night as we start a new week. thank you for being here with us. i'm brian williams. of course we hope to see you right back here tomorrow

evening. good night. good evening, thanks for being with us on this monday. i'm raj matthai. >> an emotional and compelling day in court today. prosecutors ask the jury to sentence serial killer joseph naso to death. the 79-year-old convicted last month of killing four california women. today the prosecutor showed the court just how vicious his crimes really were. nbc bay i hernandez is live outside the courthouse in san rafael. >> reporter: jessica, the jury will begin deliberating the face of joseph naso tomorrow morning.

should he live or be sentenced to death? that after a very dramatic day inside the courtroom as both sides presented their closing arguments. the prosecution says 79-year-old joseph naso is a coldhearted ruthless killer who deserves to die for his crimes. prosecutors told the jury roxene roggasch, tracy tafoya, along with women naso also killed have waited a long time for justice. in a dramatic move, ahana let a two-minute timer run to zero asking jurors to imagine what the victims went through in their final minutes as naso strangled them. >> what i wanted from the two minutes for them to be able to experience what the victim experienced as they were dying. and that's part of the consideration that they need to go through when they determine what the appropriate penalty is. >> reporter: but naso did his best to