U. S. Citizens were known to have been killed. But a number of them have been injured. At least 31 people were killed and nearly 200 wounded in the two airport bombings and another in the brussels subway system. The Islamic State claiming responsibility for the attacks. In a statement it said there will be black days ahead for the aggression against it. U. S. Officials say they believe that claim is authentic. The republican president ial candidate john kasich speaking out on the attacks, criticizing president obama for not returning to washington from cuba. And had i been president , i would have cut short my visit and flown home and i would have conducted calls jointly with heads of state and gone to assemble teams of people, Intelligence Experts who can take a look at this serious breaches that we have in intelligence. Showing solidarity, the eiffel tower lit up at dusk bathed in red and white lights and black and gold. The latest on the attacks for you, that is the belgian flag depicted on the eiffel tower. Well have updates on the situation throughout the afternoon. We will send it back down to you guys. Thank you. Lets take everybody live to brussels. Hadley . Reporter tonight this is a city in lockdown. You have trains and planes and metro still shut down. Were a few steps from the metro station. 20 killed and 130 were wounded and were just down the hill from the epicenter of european politics, where the Eu Parliament and council meet. This is an area which is really the beating heart of europe and clearly these were coordinated attacks bent on taking this out. Interestingly enough, if you look around whats happening here. This is a cordoned off area. Weve seen a heightened security presence here. Even to get here today was very difficult. We had to fly and pass over the border between the netherlands and belgium. We did see a heightened security presence along the roadway and a lot of traffic. This is a nation thats not only in mourning but a nation that is in a heightened state of alert. Theyve taken the terror alert to number four and the Prime Minister saying not only is this a very dark day for his country but also that there will be three days of National Mourning beginning tomorrow. Hadley, you reported for us of course and been on the ground there late last year. Whats the sense of the reaction in brussels relative to what you experienced last year . Reporter we have to remember that this is the Second Attack in four months in a European Capital. Theres a great sense of insecurity right now. Certainly among these leaders you have to remember this is not just center of european politics but also where nato is and place where there are multiple ambassadors and so many ambassadors as much as perhaps in new york for the united nations. This does feel like the beating heart of europe. Right now this is a city with a heightened terror alert in lockdown. With Security Officials running here and there to talk to counterparts, you have a major language barrier. A great deal of insecurity in the countrys capital. Thank you very much. Various european leaders have been coming out in support. Francois hollande saying though the attacks are in brussels, all of europe has been hit and added that europe must be careful to seek unity. Angela merkel said the German Cabinet would convene on wednesday to discuss the implications of the attacks on brussels and germany will work in every way with the Belgian Security services to find and identify and punish the perpetrators of todays crimes. The british Prime Minister, David Cameron condemned attacks describing them as appalling and savage. He expressed a desire for europe to stand together. He said the uk faced aid real Terror Threat itself and Police Presence was being increased at major transport hubs but that the Terror Threat level was not being immediately elevated from the current level of severe. Lets bring in further this discussion former cia analyst and cnbc contributor and robert less could you xi, former secretary with the department of Homeland Security. Were used to talking to you about middle east insecurity and how it affects oil. Were talking about european terrorists and talking about european instability now. This is chronic and not a oneoff situation. These are nationals. They are second and Third Generation immigrants. If you look at european countries, france has sent thousands of fighters to iraq and syria. On a per capita basis, no european country has sent more than brussels. Let me jump in. President obama making additional comments on the terrorist attacks. John . Just as the president spoke this morning before the address to the cuban people in havana, he just spoke to espn about the attacks while taking in a baseball game with raul castro, the cuban president. Heres the president s message. This is just one more example of why the entire world has to unite against these terrorists and that the notion that any political agenda would justify the killing of innocent people like this is something thats beyond the pale. Were going to continue with the over 60 nations that are founding isil and go after them. Our thoughts and prayers are with those who have been lost. In attending the baseball game where he just made the comments, the president was ignoring critics who said he should cut short the trip to cuba and come back. The president just now in further remarks said hes not determined not to let terrorists disrupt the american way of life. They cant defeat us and this is consistent with his message of not overreacting and panicking in response to attacks like this. Will be for fod der for krit he cans who said he should have left, not sitting at a baseball game in a pair of sunglasses . Exactly right. John kasich said that and that was what the president was responding to by saying they cant defeat us, not going to make us panic and yoifr reoverreact. Any additional thoughts . I think this might feel further criticism that president obama paid sufficient attention to the isis threat all along, calling it a jv team or response to syria and problems in iraq. This will play into the political discussion about the u. S. Terrorism response. Robert, also with us former Homeland Security assistant secretary. Your take on the fact that the president hasnt flown home . I mean, the president has a Great Security apparatus here, theyve been working at this more a long time. The president s presence here in the United States during this incident, i frankly think is immaterial. The leadership here, knowing these professionals, were talking about professional Law Enforcement and professional security representatives in the United States and what they need to be doing. The president doesnt need to be directing them. Do you have the same confidence in professional Security Officers in belgium, across europe who now have too deal with whether theres copy cat attacks or similar sympathizer who see the vulnerability of major European Capitals. I worked with a lot of Law Enforcement agencies in particular and they are highly professional. We do a lot of cross training between europeans both in nepal, country to country exchanges, a lot of good training that goes on. I agree they are fractionalized in belgium and may be an int intelligence issue but in terms of Law Enforcement and Operational Security aspects, they know what they are doing. This is a tough type of attack to prevent and detection and prevention are key components for Law Enforcement. I think one of the things we saw, the outcome of this event today, im speculating but quite possibly is a result of fact that they were able to make the arrest four days ago and these operatives were concerned about being active themself. They go into operational mode. Its very difficult to be able to prevent all of these types of incidents. Certainly terrorists have to be lucky once but theres been tremendous criticism for not doing enough to deal with home grown extremism and concerns about the fact the lack of cooperation between European Intelligence Services and suspects can be listed differently so you dont know if they are on a watch list. I think there are lots of loopholes that need to be closed. Its an ongoing challenge. Thank you very much for joining us. Right up next, what air travelers will be thinking and what they need to know in the wake of the terror attacks in belgium. Well go live to one of the busiest airports in the u. S. And speak with two security experts. Later, Mohamed Elerian gives his opinion on the reaction from the markets. Ear watching cnbc, first in business worldwide. Welcome back, checking on Major Airline and travel stocks following the brussels attacks, Delta Airlines down 1. 5 . Bigger declines for priceline down 2. 5. We know in turkey, for example, in the spat of many terrorist attacks, their summer bookings are down 40 . Brussels being less of a tourism destination but looking at tourist flows and business. We saw likes of easy jets, European Airlines following in european trade as well. Many on edge following the deadly terror attacks and mary, whats the sense on the ground there . Reporter well, of course, as you would expect, were seeing heightened security here at Newark Liberty as youre seeing at major airports across the country in the wake of those terrorist attacks in belgium. But we spoke with a number of travelers, most of whom were traveling domestically and said the attacks are having no impact on Domestic Travel plans but if they were travel ago broad, they might give it a second thought. What happened today wouldnt change my plans. I dont think about it. If its your time, its your time. Thats how i look at it. Now, in addition to the added security youre seeing at airports, theres added security on amtrak trains and metro stations in the major cities in the u. S. There have been 439 cancel selgss in and out of brussels and united and delta are among those who rerouted passengers. American Airlines Offering refunds to clients scheduled to go to brussels as well. On the hotel side, air bnb asking hosts if a client is in an emergency situation to let the client stay there for free if necessary. And marriott which has four properties in brussels is waiving cancellation fees if a client has to indeed cancel their reservation because of this. Whats surprising is travelers in the u. S. Are getting more used to these types of attacks and how it might impact them but they are much calmer now then they would have been a couple of years ago in large part because of the frequency of these attacks were seeing. Back to you. Lets talk more about Airport Security with anthony roman. Also a licensed pilot. Also with us, ceo of ar challen challenges, former consultant to the israeli airport authority. Are we doing enough in terms of airport safety here . Who are you asking . Go ahead, sir. Yes, i think there is a misunderstanding in the United States what you do is not Airport Security. Youre doing Aviation Security via the psa. The airports are usually secured by either the local police or some strength ever fbi. But the biggest problem is youre still looking for luggage and not looking for one of the biggest problem to train Police People and other tsa agents to really look for suspicious behavior and not going through the bottles in the security of baggage. Is that a fair point because attacks we saw this morning in brussels, on the land side of the airport, not on the air side. Theres been no security checks up to that point. What can authorities whenever they are in the world do when they havent reached security boupd rry yet . Hes spot on. Were only paying attention to a small segment of the risk. The air side risk where the fence and Electronic Security measures are taken to protect the airplanes and runway and passengers boarding from the air side is really a complete failure. Penetrations are happening every month. So its really not working out very well. On the Passenger Terminal side, cars are still allowed to pull up to the curb. You can have a propane bomb and you can have a fertilizer bomb. It would take out the entire building. There are high concentrations of large numbers of people and its a real problem they are not properly protected. Those con tragss reflect those being dropped off to catch a flight. What is the response youre recommending here that would make those points safer and how much would that affect peoples travel . If the logistics are prepared properly and roadways are changed just a little bit and there are pools of dropoff areas away from terminals, it would be better. Vehicles should not be allowed within the blast zone. Rafi, what quality are the u. S. Airport security checks versus some others in the world . Of course the tough point i suppose they have many were built decades ago as opposed to the new airports in the likes of dubai and singapore. I dont think that the buildings have anything to do with security. The security should be as follows. If the target is moving, you have to move with the target and nobody is doing this. So the best thing to do is follow the israeli program, which is the security circle. You start at the entrance to the airport and while everybody is walking towards the terminal and doing stuff inside the terminal, he has to walk through several security to see the Behavior Analysis of those people and we in israel can detect suicide bombers almost 100 . So this is a change of a disk in the thinking of the security agencies in the United States and also in europe. Anthony, coming back to attacks earlier today, why do you think brussels was the target . One would think there are more high profile potential targets heath row airport, perhaps jfk. Why have they gone for brussels . They look for easy targets and belgium is an easy target. The molenbeek area is a hot bed of radical activity and no go zone for police enmany government authorities. In addition to that, their Intelligence Services have low penetration in terms of trying to get information from the local community relative to terror cells. So thats where the problem starts. It goes back to a point you were making as well. By the way, rafi, when you talk about how we need to focus on the people and not necessarily the buildings, what additional kinds of steps has israel taken in order to be more effective in this . Do you think other reports or other Security Operations could adopt as well . Well, as i said, you have to adapt a security circle process and then you have to look at the people who are moving at the airport and patterns of behavior before you even go through the luggage if you need to go through the luggage of people, because the most important thing in security is the detecting the intent and not the bottles or Something Else that is in the luggage itself. Other countries weve seen airport personnel kplis it here. Numerous levels to keep an eye on. Thank you both. The dow is down around about 42 points, about a quarter percent and s p down a little less than that,. 1 . Well keep an eye on it with 45 minutes to go. Isis has claimed responsibility for the deadly brussels attacks, well get reaction from two medal of honor recipients and expert on Islamic State who wrote multiple books on the terrorist organization coming up. Youre an at t Small Business expert . Sure am. My staff could use your help staying in touch with customers. At t can help you stay connected. Am i seeing double . No maam. Our at t buy one get one free makes it easier for your staff to send appointment reminders to your customers. And share promotions on social media . You know it now im seeing dollar signs. You should probably get your eyes checked. Good one babe. Optometry humor. Right now get up to 650 in credits to help you switch to at t. Who dont have access to basic banking,ple but that is changing. At temenos, we use the microsoft cloud to provide banking to the millions and millions of people who need it that dont have access to it. With the microsoft cloud, we can enable a banker to travel to the most remote locations with nothing but a phone and a tablet. More and more people are getting access to credit. Everywhere where theres a phone, you have a bank. So now a person is able to start a business, and generate an income, and employ somebody for the first time. And you can actually see the success. Its transforming our world. The microsoft cloud helped us to bring banking to ten Million People in just two years. Thats potentially ten million new businesses. Technology is about breaking down barriers, removing limitations so that every person has access to opportunity. A small amount of money can change peoples lives. Its very, very powerful. Welcome back, a belgian prosecutor, Authorities Say this surveillance photo shows the suspects in the bombings. The names have not been released. Isis claimed responsibility for the attack that