nbc's mark potter starts us off from ft. hood. mark, good evening. >> reporter: good evening, brian. we're learning more tonight about the events leading up to the shooting. officials don't believe this was a premeditated killing spree. investigators say they believe shooting suspect ivan lopez acted alone after a confrontation with other soldiers. some of whom were among his victims. >> we do have credible information he was involved in a verbal altercation with soldiers from his unit just prior to him allegedly opening fire. >> reporter: nbc news has also learned lopez told friends he was angry about getting only a single day of leave for his mother's funeral. the three soldiers who are killed here at ft. hood have all been publicly identified. 38-year-old staff sergeant carlos lazaney rodriguez. after serving nearly 20 years in the military, he was planning to retire to puerto rico at the end of the year. rodriguez's aunt says his destiny took a turn for the worst. he died in the place where he loved to be. 37-year-old sergeant

our report from nbc's mark potter. ♪ >> reporter: at sunday services near ft.ood, the shooting victims and their families were in everybody's prayers. >> continue with words of encouragement. continue with prayer. >> reporter: among those feeling very grateful today is theo dus westbrook who feared he had lost his own son in the shooting spree. >> what jonathan? not my jonathan, not my son. >> reporter: his son survived after being wounded in the chest and arm by a gunman identified as specialist ivan lopez. westbrook says he was told that the shooting began at his son's human resource office after lopez got into an argument with others and was told to come back later after requesting a leave of absence form. lopez returned with a hand gun and shot three people there. >> it was like he was saying, okay, buddy, you're next without actually saying that, and my son, you know, is reading all this from the shooter's eyes. then he pulled the trigger and shot my son. >> reporter: a new aerial diagram released by the u.s. army showed the shooting spree covered a two-bl

we want to begin our coverage with nbc's mark potter at the main gate. mark, good evening. >> reporter: good evening, brian. fort hood is once again reeling from its second shooting rampage in five years, as you said, and there are many questions about why this happened and could it have been prevented. a woman who acknowledged she is the wife of the alleged fort hood gunman seen today leaving her killeen, texas, apartment. >> we have an active shooter currently on fort hood. >> reporter: the alleged shooter, 34-year-old u.s. army specialist ivan lopez, believed to have brought his own gun onto the base. >> it's going to be the 33000 block of 72nd street. we have multiple gunshot victims. >> reporter: military officials say lopez entered a building in the first medical brigade and opened fire with a .45-caliber handgun. he then got into a vehicle and continued to shoot. >> just with advised, they're saying that the vehicle was a dark toyota camry. and it was a unit, a specialist that's actually active shooting. >> reporter: next lopez walked into another

we get more on this tonight from nbc's mark potter. >> reporter: florida farmers are throwing everything they have got into a desperate attempt to keep citrus trees alive, but they are losing the battle against a deadly disease discovered here nine years ago that now threatens the entire industry. >> and if we can't whip this disease, you could possibly lose, would lose, orange juice at the breakfast table. >> that died on the vine. >> reporter: it's citrus greening caused by a tiny insect known as the asian citrus sillit. because of it, the florida orange crop this year is expected to be the lowest in 30 years. in just the last two years, the number of oranges produced has plummeted by about a quarter from 146 million boxes to a projected 110 million boxes. drastically smaller orange harvest now could mean higher orange juice prices later this year. the orange has long been the symbol of florida, and citrus is a $9 billion industry, supporting 76,000 jobs. >> pretty much every grove in the state is being affected in some way or another. >> reporter: veteran grove manager billy teal says

mark potter, nbc news, fort hood, texas. >>> a big headline a lot of us woke up to this morning, searcheams off the coast of australia have enough electronic signals from the deep now for experts to be able to say they are likely from the missing airliner's black box. the australian search commander says he believes it could be just a matter of days before they locate the actual wreckage of flight 370, miles beneath the surface of the ocean floor. our report tonight from nbc's tom costello. >> reporter: off the coast of australia growing on the miz tham search teams are honing in on the remains of flight 370. the "ocean shield" towing a u.s. pinger locator has detected more pings that sound something like this. [ pings ] now military audio engineers say those pings are likely coming from at least one of the plane's black boxes. >> hopefully, in a matter of days we will be able to find something on the bottom that might confirm that this is the last resting place of mh370. >> reporter: the area of concentration is along one of the arcs engineers identified as the plane's likely flight pa

our report on all of it tonight from nbc's mark potter. >> reporter: the moment of terror captured on cell phone video. the massive 8.2 quake knocked down buildings, triggered landslides, cut off power, and sparked fires that raged for hours. at least six people were killed. seven-foot waves hammered chile's coast, destroying dozens of boats in this fishing village. during a tsunami, authorities evacuated nearly 1 million along the coast, jamming roads for miles. recovery efforts have been hampered by cracked highways and flooded streets. authorities here have been preparing for years for the big one. [ sirens ] experts say this wasn't it, but still sirens in chile rattled nerves all along what's called the ring of fire, running from new zealand through indonesia and japan, across to alaska, and down the west coast of the americas. a zone of intense seismic and volcanic activity. the circles in yellow are large earthquakes just within the past two weeks. >> california's really too far away from chile to see anything. >> reporter: lucy jones is a seismologist helping the city of los an

we begin with mark potter in ft. hood, texas. mark, good morning. >> reporter: good morning to you, erica. about 150 investigators from the state, the fbi and army are trying to piece together this case at several crime scenes here on base. they have a long way to go, but preliminarily say they believe several things. one, that the alleged shooter, specialist ivan lopez, acted alone, that he was not linked to any terror or extremist group. they do not feel that this was a premeditated, long-planned shooting spree or that his mental condition alone sparked the attack. what they say they do believe is that the shooting followed a heated argument involving lopez and other soldiers in his unit here on base, some of whom would become his victims when it all spiraled out of control and he opened fire, ultimately killing himself. now, the three people who were shot dead by the gunman have now been formally identified by the army, and they are 38-year-old staff sergeant carlos lazaney rodriguez, who served 20 years and was about to retire

mark potter, nbc news, ft. hood, texas. >>> presidential elections in afghanistan is being held this morning despite violence at some polling stations. about 7 million afghans turned out to vote. polling hours had to be extended. it's expected to take about six weeks for results to come in. >>> so take a look at these images from nasa. they show a solar flare. flares are powerful bursts from the sun. in some cases they can disrupt communication signals. but as far as instagram goes, awesome. >>> and finally, it's hard to say what was crazier. kentucky's dramatic win at saturday night's ncaa tournament or nothing. because that win was crazy. so crazy that thousands of kentucky fans took to the streets for a little celebration time. kentucky was trailing wisconsin by two points until andrew harrison passed the ball to his brother, aaron hearrison liftin them to the win. they will now face uconn for the championship monday night. uconn had beaten top-seeded florida earlier in the day. coming up on monday nightor t

>> mark potter in our los angeles bureau. lide that took dozens of lives in washington state. a slide so big it can be seen from space as this dramatic new satellite image shows us. and the search for victims enters the 12th day. miguel almaguer has the latest. >> reporter: this is our first upclose look at the damage where 28 people have died. and this morning, 20 are still missing. from this higher elevation, you can see the hillside that just sheared off. and look at how much ground it covered. 1 square mile slid down this mountain. >> the hill didn't just slide away, the bottom blew out with an incredible amount of energy, came across this debris field and pushed all of this material. >> you can see this huge tree that's been toppled over. looks like clothes from a family draped around it. pieces of everyday life strewn everywhere. this is one of those ominous signs work crews look like they found something. they've discovered another body here, so we're going to stop shooting. it's heartbreaking work here. the teams are c

joining me now from los angeles is nbc's mark potter. mark, what are the latest details that we're getting in, regarding the assessment of damage and, of course, the fatalities? >> that assessment is under way now, and one thing i want to tell you, tamron, based on our time in chile four years ago when the big earthquake and tsunami hit, i can tell you nothing terrifies the chileans more than an offshore earthquake and tsunami warning. when they are told to evacuate now, they do not need to be told twice, and that's what happened last night. hundreds of thousands took to the hills to get out of the low country. fortunately this time the tsunami was not nearly as big as it was in 2010. the waves, six to seven feet high, and fortuitously, they hit in the northern part of the country in relatively remote areas in a copper mining country, so that kept the death toll down. as you said, six people reported killed so far, most from falling walls or heart attacks. we don't know if any are attributed to the waters coming ashore. the chilean govern

mark potter has the latest. ♪ >> reporter: at sunday services near ft. the shooting victims and their families were in everyone's prayers. >> continue with words of encouragement. continue with prayer, continue with worship. >>> monday those feeling very grateful is theodis west broom w brook who feared he had lost his only son. as it turned out, jonathan survived after being wounded in the chest and arm by a gunman identified as ivan lopez. the shooting began in his son's human resource office. lopez returned with a hand gun and shot three people there. >> it was like he was saying, okay, bud eydy you're next. then he pulled the trigger, and shot my son. >> reporter: a new aerial diagram released by the u.s. army shows the shooting spree covered a two-block area and involves these buildings. the first 911 call came in at 4:16 on wednesday, april 2. lopez then got in his car and fired at others as he drove. after being confronted by a military police officer in a parking lot, he then shot and killed himself, leaving behind three dead and 16 wounded. >> a

potter great to have you with us tonight. what does the 7 million mark mean for this law? >> it means a great deal. it means the insurance companies have the number that they were really needing to make sure the premiums are going to be stabilized and it's also, i think, low. i think we will see in the coming months that a lot more people than that would have been covered bite end of this year. keep in mind a lot of people signed directly with insurance companies, especially during the months when the website wasn't working well. is and a lot of people signed up through private exchanges, medicaid expansion. 26-year-olds, stay on their parents' policies. i'm betting by the end of the year, 15 to $15.5 million will have been newly covered. >> we needed 7 million people to make this work for the insurance striecht thought insurance industry is somewhat making -- gosh, we got all these new customer, how can we ge bee against this? what are we thinking in the front office? >> they're probably breathing a sigh of release. because they need to have substantial numbers signing up