collected from here, but blood-soaked clothes and shoes remain. this looks to be a bloody handprint. the shelter is 15 feet long, maybe 6 feet wide. the idea of so many people packed in here standing shoulder to shoulder terrified and screaming, it's incredible that anybody was able to survive. there are other shelters like this, other tragedies still to be discovered. the full horror of what happened here is just starting to come to light. anderson cooper, israel. >> you can see a new episode of "the whole story" tomorrow at 10:00 p.m. eastern. >> announcer: this is cnn breaking news. if you're just joining us,

this is cnn's live coverage of israel at war. i'm wolf blitzer in washington along with sara sidner in tel aviv. there's breaking news we're following this hour. americans and others stuck in war-ravaged gaza are on alert to evacuate potentially at any moment. the state department is urging u.s. citizens to move closer to the rafah border in the southern part of gaza crossing from gaza into egypt in case it opens up with little notice. local media reported earlier that egypt was not, repeat not, allowing american citizens through the crossing. more than 1 million civilians in the northern part of gaza are under israeli orders to flee to the south, an evacuation the united nations is calling impossible. the humanitarian crisis is escalated amid widespread destruction and a mounting death toll in gaza now rising above 2200. it's been a full week of punishing israeli air strikes in

response to the horrific and deadly hamas terror attack on israel last weekend that killed some 1300 people. the israeli prime minister benjamin netanyahu signaling a ground invasion of gaza could, in fact, be imminent. as he met with front-line israeli troops and declared they are ready for the next phase. i'll bring in my colleague sara sidner from tel aviv right now. sarah, israeli leaders have warned this war is only just beginning. >> yes. you can feel the anticipation that there will likely be the ground war that everyone has been waiting to see whether it was going to happen. we have been watching the troops amass on the border. we're talking some 300,000 reservists who have come to the border in preparation. we've also seen here in tel aviv, a city that is bursting with activity normally even on

the sabbath, this place has beaches and people are usually having fun on saturday. it is absolutely quiet. that is not normal. places are closed. people are in their homes for the most part, a very different scene than we're used to. also thousands of palestinian civilians are moving to southern gaza after the israeli military warned them to leave northern gaza for their own safety. the u.s. told american citizens also to move closer to the gaza border with egypt. the u.n. has said the evacuation of a million people in one of the most densely populated places on earth is impossible. today the u.n. condemned the evacuation order as a crime against humanity and a blatant violation of international humanity law. food and fresh water is running extremely low and quickly will run out. salma abdulaziz is following.

what are you hearing from people experiencing all of this inside gaza? >> just a few hours ago this evacuation advisory by the israeli military expired. what is clear is there are still hundreds of thousands of people absolutely trapped in the cross hairs. you mentioned the condemnation from the united nations. the u.n. is going so far as to say there are no safe places in gaza. the fear from rights groups is many families will be left out essentially in the open without shelter as bombs rain down on them. here's the situation in gaza. i warn you, this report does have graphic images 37. this is what running for your life looks like in gaza.

an ambulance rocked by explosions as they attempt to flee. it is unclear what happened to them, but they are among the tens of thousands on the move after israel's military called on half of gaza's population, some 1 million people to get south in a matter of hours. along the safe passages specified by the idf, utter horror. you are looking at the carnage and chaos on one of the designated evacuation routes. in the aftermath of explosions, families killed among their belongings. the u.n. calls israel's evacuation advisory impossible and a violation of the rules of war. palestinian officials accuse the idf of bombing civilians even as

they fled. dozens of evacuees were killed or wounded by israeli air strikes according to hamas. cnn has reached out to the israel military for comment. the victims are flooding into gaza's overwhelmed hospitals. again, it's the youngest caught in the cross fire. nearly half of gaza's population is children. what did the children do to deserve this, this woman says, did they fight you, did they fire rockets? my niece and her whole family are dead. the only survivor is a 2-year-old girl. the health care system is on the brink, a complete siege making it impossible to get aid to the enclave. already there's a shortage of everything, even space in the morgue. >> translator: we're keeping the dead in ice cream trucks so the bodies don't rot, this doctor says. gaza is in crisis. gaza needs help. >> reporter: for those still able to move south, this is one of the neighborhoods families

are expected to flee towards, where israeli air strikes have wreaked havoc. >> translator: this is a genocide, not a war. it's genocide, this man says. it's an attempt to force all palestinians out of the gaza strip. >> reporter: finding refuge is proving dangerous and deadly. for the many families desperate for shelter, the fear is there may be no safe places left. what is so alarming as you look at those images and that humanitarian crisis unfolding on the ground is that prime minister netanyahu has made it clear that this is only the beginning thof this offensive. there are hundreds of thousands of troops sitting on the border potentially preparing for a ground incursion. this is an absolute catastrophe for the 2 million gazans still

trapped inside that enclave. >> salma abdul aziz, truly disturbing pictures. we now have some breaking news to share with you just in to cnn. we have just heard from the idf that says its forces are increasingly operational readiness for the next stages of the war. when you hear that, it really gives you a sense that this is about to happen, the ground war that everyone has been wondering whether it is going forward and when it's going to happen, we are getting closer and closer with these words from the israeli defense forces. i want to go to ben wedeman who has lived and worked in this region for such a long time. i think you were on the border with southern lebanon.

what do you think this means when you hear that the israeli defense forces, the military saying it's increasing operational readiness for the next stages of the war, what does that mean to you? >> reporter: we heard the same sort of talk back in january of 2009 and in 2014 when israel in both instances did launch ground invasions into gaza. really this is a prelude for another bloody stage in this war. we know when israeli troops go in -- and there are still hundreds of thousands of people in gaza city, where the israelis perhaps believe some of those captives are being kept, where they believe perhaps many of the leaders of hamas are hiding out -- that's going to be the target. if they go into for instance refugee camps, one of the most

crowded areas in a strip of land that's already very crowded, the alleys are maybe a meter and a half wide. so getting in there and conducting military operations among these breeze block houses is going to be a bloodbath. as much as the israelis say they're going to try to avoid civilian casualties, in that environment it is inevitable there will be large numbers of civilian casualties in such an operation. >> you and i both have lived in this region, both of us living in jerusalem, but you sometimes living in lebanon. as you watch this happen, you can see this is going to be something perhaps like we've never seen before, although we have seen plenty of incursions and operations in gaza by israel. you're on the lebanese border with israel.

we have been seeing a bit of fighting coming from that border. can you give us a sense of what you've been seeing over the past couple of days? >> reporter: yes. particularly today about five hours ago we started to hear distant thuds from a disputed area between israel and lebanon. it went on for about two hours, eventually petering out. we did also hear volleys of rockets being fired from lebanon into israel. according to the israeli military, 30 mortar rounds were fired into israel initially. the israelis responded, and this set off a back and forth of fire the likes of which we haven't seen since we got to south lebanon. according to the israeli military in the process of this exchange, there was an attempt to infiltrate into israel. they say they conducted an air strike to neutralize those

infiltrators. hezbollah put out a statement saying it had struck with precision weapons israeli targets in the shall be baa farms area. local news media are reporting an elderly couple in the lebanese town of she been baa were killed when their house was hit today. yesterday we saw other action around the town of me tulle la and on the lebanese side. in that instance, a group of journalists was struck by israeli missiles, one of them a friend and colleague of many of us from reuters. a camera manman with much expere in the region was killed and six others were injured. >> our hearts go out to our

colleagues the journalists and others killed in the region. ben wedeman, you're such a wealth of information. thank you so much for your reporting there on the lebanon/israel border. let's send it back to my colleague wolf blitzer. >> sara, our special coverage will continue after a break. .

joining us, the former israeli prime minister ehud olmert. it's been a week since that truly heinous hamas terror attack on the people of israel. what's your assessment of how the government and military have handled the response? >> i think the real response hasn't started yet, wolf. it's about i don't think there

will be one message on ground right away. it needs to be done in a very careful manner in order to target -- [ no audio ] >> i think our connection is not good right now. we'll try and strengthen it and get back to the former israeli prime minister. let's take a quick break.

there are growing signs right now that israeli troops are about to move on gaza. we are watching this very closely. we're also trying to reestablish our connection with the former

israeli prime minister ehud olmert. we'll get that reconnection going. our interview with him is coming up. there are important developments we're following right now, including anderson cooper, who has gone inside that music festival that was attacked by hamas. it's a very, very powerful report. we'll have more on that coming up as well. meanwhile, cnn is learning new details about that music festival where some 260 young people were killed in that hamas terror attack. as questions mount overall of this, the question remainiremai was hamas able to launch their surprise attack with such precision? u.s. intelligence warned of the potential for violence days before that attack by land, air and sea. peter bergen is joining us right

now. peter is a security analyst and was the vice president for global studies and fellows over at the new school. peter, are you there? unfortunately,we have lost our connection with peter bergen as well. we'll reconnect with him and ehud olmert. let's get our act together. we'll be right back.

all right. we are back with more breaking news. there are growing signs that israeli troops are nearing a potential ground invasion into gaza. the very latest just moments ago, israel's military says its forces are -- and i'm quoting here -- increasing operational readiness for the next stages of the war. we have already seen the war raining down on gaza from the sky. now it appears the next stage

may be a ground offensive. the statement comes as israeli forces continue pounding targets from the air as tens of thousands of palestinians in gaza rush to flee their homes after israel ordered more than a million civilians to evacuate to the south. a new window given by israelis for safe passage expired just a short time ago. i am joined by retired army general wesley clark. he is a cnn military analyst and the former nato supreme allied commander. general, i'm so glad you're here to talk with us, because we've gotten some new information. i want to read once again the exact wording of what the idf are saying at this hour. they're saying, quote, there is an increasing operational readiness for the next stages of war. what does that mean to you specifically?

>> it means they're going through their troop leading procedures prior to crossing the line of departure. this means they'd be issuing rations. they'd be giving their objectives for the various subordinate units from the brigade to the battalion to the company to the platoon. they're working on their radio communications, exchanging frequencies and alternate frequencies. they'd talk about where the logistics is coming from. they'd talk about how they going to move from their current assembly area to their position for departure, all standard troop leading procedures. >> this is such a difficult spot for the civilians to be in in gaza. you had this surprise attack that happened to israel that no one saw coming, intelligence-wise at least here in israel and from the u.s.

and now you know an attack is imminent. you know a potential ground invasion is coming after there have been multiple strikes from the air. how do you deal with this on the grou ground? if you're a civilian, there's no doubt in your mind that civilians are going to face -- >> sure. you have to understand that hamas knew all of this. hamas planned at least a two-phase, maybe a three-phase operation here. the first phase was going to israel, kill as many people as you can, make them as mad as possible and invite them to attack on the ground. second phase, let them come in, keep your civilian population in place, use civilians as human shields, get the world's press attention on it, show how inhumane the israelis are, use world opinion against the israelis. if it takes three weeks, four

weeks, five weeks and the israelis get really bogged down, maybe hezbollah will even come in from the north and maybe even iran. but at the minimum, what you've done is you've shown up in front of world opinion the israelis. hamas is deliberately doing this. they're deliberately putting 2 million people at risk. they're deliberately using the civilians as human hostages. when i see the united nations secretary general talking about crimes against humanity, it's hamas that's starting the crimes against humanity. this was a terrorist act. it was a slaughter last saturday. it was done deliberately to provoke what the israelis have no choice but to do. they can't live with this. they can't let this threat persist on the border of their country. so everybody knew what was are going to happen, especially hamas knew. so i think the condemnation starts with the condemnation of

hamas. this is an organization that was created with the express purpose of eliminating israel. so the people that voted for hamas knew what they were voting for. maybe some of them were coerced into it, but hamas is a militant terrorist organization. it's not an alternative governm government. it's not the palestinian authority. it's not someone you can reason with. i think we have to understand this is a war not only on the ground in gaza, but a war of global opinion. right now on cnn one of the battlefields this is what it's about. it's the american public, the global public watching this and saying, what's happening, why and who's right, who's wrong and what can be done on this? the simple fact is it began with hamas. israel is going to do what it has to do to survive as a state. hamas is dedicated to the

destruction of israel, using its own civilian population as hostages and weapons in this war. it's a totally immoral, terrible approach. i hope it will receive the global condemnation that it warrants. >> i do want just to mention quickly before i ask you another question as we look at live pictures of gaza, you can see it is completely dark with the exception of just a few lights there, because israel had a blockade. they have cut off electricity, water, food to the area. israel says, look, we have cut off the electricity in particular to try and stop hamas from being able to operate at its normal operation trying to build things, rockets, sending them over. this ground incursion, if it happens or when it happens, what are the goals for israel as they

go into this? one of the things i have heard having lived here for a while in years past is that israel doesn't want to rule or be the ruler of gaza. they don't want to have to deal with ruling gaza. so what is the end goal here? what do you see having to happen if there is this ground offensive? >> well, i think when they go in, the objective is going to be to eliminate the military potential of hamas. that's both the weapons factories, the tunnels and any hamas fighters, and there are probably 20,000 of them who will remain in gaza. it's going to be a tough fight. i think the israelis will do everything they can to avoid civilian casualties. they know the world is watching. they've been talked to by various governments. but they're going to do what they have to do to survive as a

state. they're going to try to apply the laws of land warfare to this. when they finish, what they're going to hope is they've eliminated hamas and its ability to come back into power. they are going to hope that the palestinian authority with backing from jordan, from saudi arabia, from other gulf states will be able to step in to the positions in gaza with global assistance on rebuilding and so forth and create a viable entity there that can engage in peaceful talks and hopefully move toward a two-state solution. >> i've been in gaza myself during an incursion or an operation, as the israeli military calls it, where there were air strikes happening after rockets had come over from hamas, but this is a whole different thing. israel has declared officially a war, which has completely

changed the tone and tenor of what is about to happen. you have that happening on the south on the southern border with israel, but you have something else happening now on the northern border with israel. how concerned are you about this war potentially expanding beyond israel and hamas and including potentially hezbollah, who are in lebanon? >> there's certainly a potential for it to expand. this is why the united states has moved its aircraft carriers in there as a warning to iran not to pull a trigger on this. but it will depend really on the effectiveness and efficiency of the israeli military operation in gaza. if it's relatively smooth, relatively quick and goes in and accomplishes its mission, has support from the international community in terms of next steps of replacing the governance and

so forth, it's no problem. if it gets bogged down, if reenforcements have to be sent in, if it drags on and drags on, maybe the mullahs in liran will make a mistake and decide this is their moment. you know, we say it's terrible that israel has declared war on hamas, but iran has declared war on israel for years and at every step declares it's committed to the total destruction of israel. vladimir putin has declared war on nato. his people say, you know, this is a fight by russia against nato. we don't say that, because we don't want that to be the case. but in the case of israel here, they're in a battle for their survival. they know it. it was a horrific attack that was perpetrated last saturday. they're in a battlefield that as

americans we have a hard time appreciating. they're going to do what they have to do to survive. >> there is a long history of this fight between particularly hamas and israel. after the attack that we haven't seen the likes of in 75 years on israel, the response, everyone knew, was going to be a very, very strong response. there are so many people worried about what's going to happen both in israel and in gaza as well as the west bank. thank you so much for explaining to us and bringing us through the history and what this may mean militarily. i appreciably appreciate your time, general clark. >> thank you. i'm going to toss it back to my colleague wolf blitzer. right now the united states is ramping up efforts to bring

miles p american citizens home. more flights are expected. priscilla alvarez is joining us from the white house. what is the coordination like to try to bring these americans home? >> reporter: this is an effort by the state department to work with airlines and international partners to provide assistance to american citizens who may want to get back to the united states. as you mentioned, just yesterday the white house confirmed the first charter flight had departed and arrived in athens. this ongoing effort includes these flights going to destinations in europe and using u.s.-based carriers to ferry these people back home. john kirby told reporters just yesterday there are more flights anticipated in the coming days, but they are also looking at

other ways either by land or by sea. we have heard from the state department there are more than 20,000 citizens who have reached out to the state department since last saturday. not all of those peoplelook looking for transportation out of israel, but it goes to show there is a demand here and a need for the state department to step in as there are limited flights to the region. all of this is ongoing. what has been very clear from the national security council is that as there is demand, these flights are expected to continue and the state department is taking critical role in the coordinating of all of that. >> priscilla alvarez at the white house for us. for more information about how can help humanitarian efforts in israel and gaza, go to cnn.com/impact or use your mobile device to scan the qr code on your screen. we'll be back in a moment.

as questions mount over how hamas was able to launch its surprise terror invasion of israel last week, cnn is now learning that u.s. intelligence warned of the potential for violence days before the hamas attack against israel by land, air and sea. cnn national security analyst peter bergen is joining us now to discuss. he's the vice president for global studies and fellows at new america. he's also the author of the important book "the rise and fall of so youosama bin laden."

we know of at least two intelligence assessments warning of potential violence by hamas just before the attack, but those assessments didn't mention the scope abehind hamas' brutality. >> go back to the yom kippur war 50 years ago. there was intelligence of the possibility that egypt and syria might attack israel at the time. but the assumption from israel policymakers is israel and s sya would not launch a war. there were assumptions made by hamas that hamas was quiescent because they were getting aid from qatar, from egypt, that gazans were working inside israel and that hamas wouldn't do anything this big. i think there were these intelligence warnings apparently also from the egyptians, but i think they were sort of ignored

because they didn't fit the assumptions policymakers had about what hamas might be capable of. >> u.s. officials, as you know, are still weighing to what are extent iran was involved in the hamas attack against israel. what will it take for the u.s. intelligence community to make a complete determination on this very, very sensitive matter? >> that is a very good question. i imagine that what would be the most useful would be signals intercepts that nsa goes back over periods of the last several weeks and see if there's any kind of signals intercepts that indicate some kinds of heads-up or bank transfers or anything of that nature. so far, despite a week out from this terrible tragedy, we keep sort of hearing the same thing. other than a report in the "wall

street journal" relatively early on, there doesn't seem to be the smoking gun other than the fact that iran in a general sense has supplied weapons, intelligence and support to hamas in the past. >> a lot of israelis are being held hostage, other nationalities as well. the lowest risk option is to negotiate for the hostages' release. what would it take for that to happen and how dangerous are the alternatives with the israeli military having to rescue the hostages directly inside gaza? >> the most dangerous thing that can happen to hostages is a rescue operation. often the hostage takers will kill the hostage. even something as skilled as u.s. navy saleeal team six can

inadvertently kill the hostages. in doughha, the qataris have so leverage with hamas. they've been giving hundreds of millions of dollars a year to poor gazans in recent years. so the hope is they could negotiate some kind of release. will that happen in the present context? i have no idea, but certainly that would be the safest approach to get the hostages out. >> you're an expert on terrorism. as all of our viewers know, we've been talking about these issues for so many years as israeli forces prepare for a ground incursion >> they'll be up against the tunnel system, which we've discussed a lot. they'll be up against the fact that hostages are being held. they'll be up against the fact

that they're effectively human shields. they'll be up against the fact that hamas has had a long time to plan, not just this moment, but in general. it's not the first time israelis have gone into gaza. we've got a group of people who are clearly prepared to die in hamas, particularly the kind of main unit that carried out this attack. these are fanatical fighters, and of course you're fighting in very confirmed spaces and urban warfare. we saw that against isis, it can be tough and it can take months. >> good points, indeed. peter, thank you very much. meanwhile, stories of heroism are emerging as we learn how israeli citizens put up fierce resistance against the hamas intruders as they invaded their homes. in one such story, a 72-year-old israeli paratrooper led local

residents in a revolt when invaders approached their kibbutz last weekend. cnn's matthew chance has the story. >> reporter: the attacks by hamas were a bloodbath, israelis slaughtered or taken hostage. >> translator: the kibbutz near gaza, the militants met their match. >> i always thought you should never catch me with my underwear. >> never catch you with your pants down? >> never. >> reporter: he suffered wounds and an amputated leg. when fighters tried to breach his kibbutz, which war veteran swung into action.

>> i decided to take my car. i take a few magazines with me. i decide to do as much as soon as i can. i saw them over the window. >> you drove toward the attackers and started shooting at them before they came through the fence? >> before. in my head, that was the only way to stop them. >> reporter: in nearby jewish communities, hamas attackers ran amuck in a vile killing and kidnapping spree. this kibbutz, home to more than 400 israelis, the small team of armed volunteers kept the militants at bay. his wife at his bedside, told me she has no doubt why.

>> your husband? >> my husband. 20 years he's in this position, and every time that a lot of young people are coming, the same position, they laugh at him. they said that he's crazy. they said that he's speaking nonsense. nobody will come. he defended the kibbutz year by year, and all the people laughed at him. >> they laughed at him, they said he was paranoid, they said it's not going to happen? >> it never will happen because we have the army. >> reporter: in fact, the israeli army came under attack by hamas, too, leaving the team to fight alone for more than six hours, way longer than expected. >> where is the army? they teach us if something

happens, i always tell my friends, we've got 35 minutes, that belongs to us. after 35 minutes, the army should be here, the unit should be here, et cetera. >> but they didn't come? >> reporter: as israelis elsewhere were taken hostage, the communities overrun, he fought on, severely injured and out of ammo, armed with just a blade. >> i said, if it should come, you should find me with a knife. >> reporter: a stubborn determination, his friends and neighbors say helped save them from the grim fate of others nearby. matthew chance, cnn, jerusalem. >> our special thanks to cnn's matthew chance for that report. what an amazing 72-year-old

former israeli paratrooper. our special coverage of the conflict between israel and hamas will continue just ahead. we'll be right back after a quick break.

this is cnn breaking news. >> there's more breaking news this hour in israel's war against hamas. i'm wolf blitzer in washington, along with