we're covering breaking news tonight of an air disaster, the crash of malaysia airlines flight 17, a commercial airliner which the u.s. says was shot out of the sky by a surface-to-air missile over ukraine with 295 people on board. tonight, the investigation. who is to blame? a field of wreckage in the middle of a war zone. and more breaking news on a second front, the ground invasion now under way in gaza. israeli troops are on the move. richard engel is there. our "nbc nightly news" special coverage begins now. a special good evening to our viewers in the western half of the country tonight. two major stories as we come on

the air this thursday night. first, the downing of a passenger jet over ukraine. a malaysia airlines 777 wide body from amsterdam to kuala lumpur. u.s. intelligence has concluded it was shot down by a surface-to-air missile. it came down in pieces without a distress call. the wreckage landed in the middle of a war zone. 298, the revised number of souls on board, all feared dead. it is almost too early to think about the international ramifications of this. hours after the crash came the news from gaza. israeli soldiers, ground troops, infantry, armored mechanized combat engineers, all on the move in a ground invasion in the gaza strip. we are going to stay on the air for an hour tonight. if your nbc station does not carry our second half hour, it will stream live on our website. with our team in place, we begin our coverage tonight with the downing of this commercial airliner. the second disaster for this airline and emerging human

disaster, of course, for the loved ones of those on board. tom costello has been covering all day from our washington bureau. hey, tom, good evening. >> hi, tom. hi, brian. intelligence sources confirming to nbc news the u.s. has evidence the plane was indeed shot down by a missile while flying at a high altitude over eastern ukraine near the russian border, an area that for the past few months has in essence been in a war zone. amateur video from eastern ukraine captured the thick, black smoke billowing from the plane's wreckage. on the ground, the intense fire left a scorched landscape. but the distinct markings left little doubt this was a malaysia airlines boeing 777. this photo shows the actual plane just after flight 17 took off from amsterdam's schiphol airport bound for kuala lumpur. ukrainian controllers lost contact with the plane. the ukrainian government quickly said the plane had been hit by a surface-to-air missile at 33,000 feet. at the time, the plane was over

contested territory in eastern ukraine, only 31 miles from the russian border. eyewitnesses on the ground reported seeing what looked like a missile, then an explosion in the sky. >> translator: the shooting was pretty intense before that. i heard a lot of noise in the sky, and i heard several shots and a strong bang. >> translator: i was inside my house when i heard two explosions. i ran out and saw black smoke everywhere. i thought that the house of my nephew was hit. i ran out and everything was just black, on fire. >> reporter: ukrainian authorities reported the wreckage was scattered over a nine-mile area and included very large pieces of the fuselage. to aviation experts, that suggests the plane likely came apart in midair. >> this is a high probability that the airplane did suffer some sort of in-flight breakup. now what the cause of that in-flight breakup could be one of two things, either it was damaged due to a presumed missile strike, or because the airplane was descending at a very high rate of speed, it

could have been aerodynamic forces. >> reporter: the ukrainian government immediately accused russian-backed separatists of firing a soviet-era missile to bring the plane down. the wreckage now lies in territory held by the rebels who have reportedly already recovered the plane's black boxes. in recent weeks the rebels have shot down several ukrainian military planes. today ukrainian authorities released audio recordings of what they claim are radio transmissions between a russian major and a russian-backed rebel named greek. >> reporter: but today the rebels denied they shot the plane down and accused the government. while u.s. airlines were warned in april to avoid flying through the region, the airspace was not closed to air traffic. late today the malaysian prime minister demanded that no one should interfere with the investigation or disturb the crash site.

>> if it conspires that the plane was, indeed, shot down, we insist that the perpetrators must swiftly be brought to justice. >> reporter: we mentioned that u.s. airlines were with advised months ago not to fly over the area. today a large number of international airlines said they will no longer fly into or over ukrainian territory. brian, late word, the victims come from about a dozen countries including some of the world's top medical researchers headed to an aids conference in australia. no confirmation on whether any americans were on board. >> all right, tom costello in our d.c. newsroom, starting off our coverage tonight. tom, thanks. let's go to the pentagon, our correspondent there, jim miklaszewski. jim, i have been hearing descriptions all day of this type of missile thought to have are brought it down, first designed in the soviet era, upgraded since then. flies over the speed of sound,

and really 30 seconds from launch to the destruction of a commercial airliner, and they're not designed to miss. >> that's exactly right, brian. it was a powerful missile that struck the malaysian airliner. and ever since last february when russia appeared ready to invade ukraine, spy satellites, u.s. spy satellites have been trained on the russian-ukraine border. and u.s. officials say that vigilance paid off today when the u.s. detected a missile launch that brought down that malaysian airliner. an infrared satellite that detects heat signatures like explosions first detected the launch, then the blast as the missile hit the plane. the weapons are russian-made anti-aircraft missiles. four missiles mounted on a revolving turret launched from an armored vehicle with high-tech electronics. the missile is 18 feet long. it's guided to the target by radar, has a range of 25 miles and 46,000 feet altitude. so fast you can't see it coming

with the speed of nearly one mile per second. u.s. officials say that a ukrainian military plane was shot down earlier this week by that same kind of weapons systems. now u.s. officials are confident that it was a missile that shot down the malaysian airliner, but they're not sure who fired the shot. now according to u.s. officials, analysts are poring over all the intelligence tonight to figure out whether it was ukrainian separatists or russians who fired the shot. but quite frankly, whoever pulled the trigger, it was still a russian weapon, brian. >> all right, jim miklaszewski at the pentagon tonight with what is known from there. jim, thanks. let's bring in michael leiter, former director of the national terrorism center. he served on the national security team in the white house under both presidents bush and obama. he is these days an nbc news security analyst. michael, let's talk a little bit first about how the u.s. knows what it knows, the so-called eyes over this region. how can we tell when there has been a missile launch?

>> brian, as jim noted, since the uprising in ukraine, the u.s. has really focused intelligence resource on this region. and it has tools, satellites and other tools that can both detect those launches from the missile by heat blast from the engine, but also the radar emissions from that system that would track the plane and ultimately guide the missile. combine that with the human intelligence coordinating with ukrainians, and all of that i think will give the u.s. a pretty clear picture of what happened and where that missile came from in rather short order. >> since you spent so many years on the national security council in that structure in the situation room, what do you reckon has been going on all day in the west wing of the white house, especially where the u.s., its intelligence gathering operation and its allies are concerned? >> when something like this begins, it is really quite

chaotic to begin. everyone is looking for information. and immediately engaging the ukrainians, talking to our nato allies to see who has what. but because this, i think, is going to be a relatively easy intelligence problem to solve, they're going to quickly move from who did this to what the policy response is. and the meetings will be about what sort of pressure should there be with nato, with our allies against russia, what should we be doing against the separatists in ukraine, assuming that's who fired this missile. >> as we said, it's almost too early to talk about the repercussions here. michael leiter with us tonight from bwi airport in baltimore. michael, thank you as always. we now want to bring in nbc's katy tur. she is at the airport in amsterdam where this flight originated and where, of course, families of the victims now are gathering. katy, good evening. >> a number of families of victims gathered earlier today. they were from europe, asia and

australia, the people that were on that flight. but most of them, 154 of the 295 on board were dutch. they were from this country. and as you said, family members and loved ones came here to schiphol airport in amsterdam earlier today to look for answers, find out anything, whether or not their loved ones were with, in fact, on board. but they were swiftly taken away from reporters and to a local hotel. not many of them showing very much emotion in the process. we did hear from one woman, though, who was holding a baby. she was supposed to be on that flight but missed it at the last minute. and as you can imagine, she was very shaken up. >> i'm -- like i'm shaking. i don't even know what to do. and i -- i feel physically sick. coming through the airport in the taxi, i was just crying. i'm just thinking that i feel like i have been given a second chance.

so hopefully we'll get there safely and i can see my family again. >> reporter: meanwhile, over in kuala lumpur, malaysia, an eerily similar sight to what we saw months ago. family members crying out, demanding answers from both the malaysian airline and the malaysian government, but getting frustratingly little. also, disturbing reports out of malaysia tonight that as many as 80 children could have been on board that flight that has not been independently verified by nbc news. but if it is true, just another disturbing layer to this already horrific story. brian? >> and what an awful period now begins for these families. katy, when you were covering the yet unresolved previous malaysian air disaster, i know you took this exact leg, this exact flight. and adding to some of the confusion today for the families, it's a so-called code share. you can book it under klm royal dutch airlines or malaysian airlines. so some of the families didn't know exactly where their loved

ones were flying. >> reporter: and it didn't come out until later in the afternoon, your time, that it was a klm share. and that's why you're seeing a lot of confusion as to whether or not those family members were on board. on that flight that i took, i can tell you, there were a lot of families, a lot of people that weren't just from the netherlands or malaysia, but others that were flying on to other locations, vacations. also places in australia. so you're going to get a lot of people from a lot of different nationalities, and a lot of confusion as to whether or not they were on that flight. because it does carry different numbers for different airlines. that should be getting resolved, though, as time goes on. brian? >> katy tur at the airport in amsterdam tonight for us, katy, thanks. these twin crises we're covering came on a day of unrelated travel for the president, who was then of course immediately in touch with his national security team back at the white house. our senior white house correspondent chris jansing has the latest from there tonight. chris, good evening. >> good evening, brian.

in fact, we just got word that the president late today did secure calls with both the national security team for the latest on the crash and with secretary kerry on the plane and the situation in gaza. both of those calls taking place on the ground in new york where he has two fundraisers. now this morning the president was on the phone with russian president vladimir putin when the first reports of the crash came out. and toward the end of that call, it was president putin who brought it up. the main reason for that call, which had been requested by moscow, was to talk about the tougher new sanctions the u.s. imposed on russia just yesterday when president obama specifically cited the movement of heavy weaponry across the ukraine-russian border. later, aboard air force one, the president called both the prime minister of malaysia and the ukrainian president poroshenko pledging u.s. support in the investigation. and then he said that the priority was confirming whether there were u.s. citizens on board.

it was vice president biden, however, who gave the first administration indications that there was apparently no accident. >> i say apparently, because i don't have the actual -- we don't have all the detail yet. i want to be sure of what i say. apparently, have been shot down. shot down, not an accident. blown out of the sky. >> white house officials now confirm that the u.s. is sending assistance with the investigation to determine the cause of the crash. that would be on recovery, reconstruction, black box analysis. and while the president said earlier today the first priority is determining whether americans were on board that plane, clearly, it's a slow process. it's one they have to get right. there are a lot of meetings going on. there have been throughout the afternoon in the white house, trying to determine that. and one more thing, i asked if there was any consideration of not attending fundraisers tonight. a senior white house official said simply we are sticking with the schedule. brian? >> all right, chris jansing on an otherwise beautiful july evening on the white house north lawn. chris, thanks.

we'll take a break here. much more of our coverage of the crash of this malaysia airlines flight 17 ahead. and then as we mentioned, our other breaking news story ahead, the start of the israeli ground invasion of the gaza strip. it just started tonight. we'll get a live report from there from nbc's richard engel.

we're back now. and as promised we move to our other major story after this ten-day back-and-forth air war, israel launched a ground invasion of the gaza strip tonight. this is a major escalation. flames and flares and outgoing fire were visible in the night sky over gaza as soon as troops got the order to move. israel announced the ground operation after talks aimed at some sort of cease fire broke down. in response just tonight hamas said the israeli invasion would "have dreadful consequences."

our chief foreign correspondent richard engel is in gaza tonight. richard, good evening. >> reporter: good evening, brian. every few moments now we can hear explosions here in gaza. we've seen fireballs in the distance. right now i can hear israeli drones in the sky. israel says it decided to launch this ground invasion after hamas fired 1,500 rockets at israel in just the past ten days. now, israel says it is using a large force including infantry, artillery, tanks, combat engineers. this operation is just a few hours old. it began late at night. and so far has all been under the cover of darkness. the ground invasion began with israeli strikes on several sides

of gaza, from the north and east, and from the sea. we watched the tracers from israeli guns firing over gaza. they show where the rounds are going. illumination flares were shot over gaza city, the most densely populated part of the gaza strip, home to nearly 2 million palestinians. the flares help israel target as drones circle the city. israel said its ten-day military offensive against hamas has "entered a new phase." it's unclear how long it could last. israeli officials suggested two weeks. the immediate target israel said are tunnels dug by hamas from gaza into israel. israel says militants use the tunnels to sneak up on and attack israeli towns. today, israel released footage it claims shows about a dozen

militants trying to approach an israeli town. but when they hear a drone, they head back underground. israel called in an artillery strike to destroy the tunnel. just a few hours earlier today there had been talk of a cease fire. in fact, for a few hours there was a brief humanitarian pause. it may be the last pause in the fighting gaza will see for some time. hamas has already begun to respond to this ground invasion firing more rockets tonight into israel. this ground invasion clearly will set back hamas' offensive capability. but it still has several thousand more rockets that can still fire. brian. >> richard engel reporting tonight inside the gaza strip, the start of the ground war. this escalation which of course would be our lead story on any other night. richard, thanks. we of course are back in a moment with more of our breaking news coverage of this crash of malaysia airlines flight 17 in ukraine.

we're back now with more of our breaking news coverage of this crash of malaysia airlines flight 17. and we want to bring in one of the foremost accident investigators in the world, debra hersman, who until stepping down earlier this year was the chairman of the national transportation safety board. she's with us tonight from our chicago bureau.

debra, this is a grisly business in the best of circumstances, but in this case you have let's say five or six miles worth of wreckage that's come down in an active war zone. we've seen pictures of firefighters putting water on it, people walking on the wreckage in flip-flops, local farmers in boots. how do you begin to assess what you have there if you're running this investigation? >> you know, investigators like to identify some really critical parts first. you want to identify the origination of the breakup, where the sequence started. so just like when they put together the pieces of the shuttle across multiple states, it's that trajectory that you're trying to take a look at. finding all four corners of the aircraft, the nose, the tail and

the two wing tips. and most importantly those recorders, the flight data recorder and the cockpit voice recorder. so that's kind of the road map that they're going to be looking at over the next 24 to 48 hours. >> and this is land being fought over by two factions where local folks were the first to respond. do you worry about some of that getting torn up and the scene getting compromised? >> absolutely. when you go into an active war zone, you're concerned first about first and foremost about your people that you might be putting on the ground there. but then you've got to think about the evidence and the wreckage recovery. and for sure you want to think about those family members that have lost loved ones. the recovery of the human remains and the personal effects, that also has to be a priority too. and so there's a lot going on here. and it's a real challenge for anyone, but particularly for a country in a war torn area like this it has got to be a double burden. >> debra hersman, these days the ceo of the national safety council with us from our chicago bureau tonight. debra, as always we appreciate your time and expertise. we will take another break. back with more of our continuing breaking news coverage right after this.

again, here tonight we've been covering these two major stories both involving loss of life, the shooting down of a 777 in ukraine, the ground invasion of gaza by the israeli army. many of you depending on your local nbc station will be with us now for a second half hour of

special coverage. if your station moves onto other programming, you're able to watch our second half hour streaming live on our website nbcnews.com. again, that will do it for our first half hour of coverage here tonight.

f starting with the apparent shooting down of a malaysia airlines 777 passenger jet over ukraine. here is what "the new york times" has written tonight, quote, headphones and computers were scattered throughout a field of sunflowers. in another field, a dutch passport lay open. bodies fell from the sky looking like rags or clumps of ash. end of quote. that's what's left of a massive wide bodied jet and 295 souls on board according to u.s. intelligence it was a surface-to-ais