new terror plot from down at one of the busiest construction site on earth. if that's all it were, a construction site, it would be remarkable. it's much more than that. along with a new transportation hub and two enormous skyscrapers up behind me, there's a remarkable memorial, the 2,606 people killed here almost ten years ago. and ten years later, all over manhattan, washington, d.c., there are echos of that terrible day. police and troops and the assault rifles and the train stations, the same as it was. check points and roadblocks pulling over trucks and vans and the anniversary to breaking news tonight. new developments of the potential plot targeting new york and washington. two of the three people thought to be connected to it are american citizens. susan candiotti working her sources. she joins us now. and a volunteer for george w. bush, and national security analyst, peter bergen. last night we thought it was just one person was a u.s. citizen, now we're hearing two. >> which adds to the information we have on that. how much more do we know? not that much. what we are hearing and continuing to hear is that there is not that much specific information abtheout these peop. their names are more common ones than we had learned, making it difficult to track them down. and as well, trying to figure out where the plan but, where they intended to go, where they went to the united states, went overseas, for training possibly, only to get back here after getting some directions from whoever was telling them what to do. >> fran townsend, you're learning new information. what are you hearing? >> anderson, the three people that we're -- they're looking for that susan candiotti was speaking about, they now have lead information that one of those people is already inside the united states. that, of course, in that they are very much just as your picture suggests, focussed on a truck bomb based on intelligence. they're working together to assess the threat together. while we heard off times in my career, tensions between the two, both sides report there's complete transparency, they're working the threat together, and they're holding back no details from one another. >> we're hearing about a possible method of attack as well? >> that's right. we saw the pictures today all over new york of trucks and large trucks being searched coming over the bridges. there's reason for that. intelligence has pointed them in the direction of focusing on a vehicle-born improvised explosive dwils or a car or truck bomb. there are gaps. there's some weird things on this. that's why there's so much focus on getting the information. the senior official up in new york said to me, even with that, even though there are source and the timing is right, we believe this has the ring of credibility. we just don't know enough yet. >> we're showing the pictures. it was interesting in new york today on a number of sort of choke points, the police set up check points where vehicles stopped traffic. traffic slowed to a crawl. all traffic had to move for one lane and they searched where they wanted to. what does it -- does any of it sound more or less credible than when we spoke last night? >> susan has spent time in the sto story considerably in the last several hours. the story sounds similar in the plot that involved an american citizen trying to blow up a bomb in the manhattan subway around the eighth anniversary of 9/11. you may recall that produced quite a reaction from the fbi and your police department. he, of course, was an american citizen living in denver. and he was intent to blow up an suv in times square on may 1, 2010 by faisal shazad, also an american person. in one case, it was a personal type plot, with the other, it was a taliban-type plot. the suspects may have travelled to the afghan-pakistan border region. so it has the ring of credibility because it seems similar the more we know about it to other plots which are being somewhat fairly serious and are being broken up in to the past, anderson. >> fran, vice president biden talked about how the main concern has been over a lone wolf type of an attack. this sounds like something more than that. like they're traveling to the pakistan border. >> that's right. this is the threat emanates out of the pakistan region. we heard that from multiple sources. when i go back and think of the east african embassy bombing, two people are in the car, one other -- the third person, is there to cause a distraction so the car or the truck can get to the point where they want to explode it. it's also true they exploded a bomb in afghanistan inside the hotel there. this is kind of how al qaeda does this it. the number of operatives, the notion it may be a truck bomb, you look at intelligence and looked at the intel general in the last decade. >> i talked about the bombing in iraq years ago and looked at the locations where we stayed. it wasn't just one truck bomb, it was two. one would come in, explode, then another one would come in. do you recall that? >> that's how -- i'm facing it on the name of the hotel. the palestine hotel, i believe. >> and kills quite a number of people. pulling the attack off in the united states. it's getting twice as hard to do. in iraq, it's a lot easier to do that kind of thing than it would be here. >> we know it was hijackers and a unknown number of planners. what does it say about the size and scope of al qaeda right now? >> the size and scope is more than what it was on 9/11. but i clearly -- this plot -- if everything was concerned, would have a controller on the afghan-pakistan border. suggests that al sa s al saah w number one. if they can't get one thereupon on the tenth anniversary of 9/11, they have to show the flag at some point. documents recovered at the bin laden's compound that the tenth anniversary was a complete obsession with him and here we have something that appears to be the fruit of that obsession. >> fran townsend, susan candiotti. follow me on twitter @anderson cooper. the problem that caused the first responders' lives here. the president recommended changes. all these ten years later, new york and other place s places wn hunt for a mullah that gave al qaeda free reign in his country. we'll look for mullah omar. than ever before, prudential's challenge is to help everyone have the retirement income they'll need to enjoy every one of their days. ♪ prudential. bring your challenges. welcome back. we're live at ground zero. an extraordinary team. one of the towers. if you have not been down here in a while, you should come. it's truly remarkable, particularly at night. the breaking news tonight, new york, washington on alert and on edge as authorities work to unravel a possible terror plot that sets the stage for our next story. a life threatening problem ten years ago. keeping them honest, ten years later is a problem today. something that's simple to fix. while not exactly cheap, the solution would cost a tiny sliver of the $600 billion spent on security since the 9/11 attack. ten years, a communications problem is only partly solved. the lives are in jeopardy because of that. take a look, hundreds of fire fighters and police officers were inside the north tower of the world trade center when nypd chopper crews advised commander osen the ground to evacuate the building. it reached police inside but uh not fire fiegers. >> the reason they didn't come down is because they didn't get the message. the only acceptable reason that they didn't come down immediately is because in my mind they were helping civilians get to the stairway and down the stairway. other than that, i'm sure if they had heard the command to evacuate, they would have evacuated. >> they didn't hear the warnings, they couldn't. the radios didn't receive police channels. we all remember the bodies being recovered from the pile. 23 police officers lost their lives. the death toll on firefighters, 343. some of them couldn't communicate with commanders on the ground. all of them couldn't listen in on police frequencies. many of them were standing up the stairs and not down and out to safety as the towers collapsed. in 2004, the 9/11 commission identified the communications as a serious problem to contributing to the loss of life. no federal action was taken. so local police and firefighters can communicate with one another, but not with any other responders that might rush in from outside of the new york area. even with the improvement, the systems are primitive. today, a 16-year-old with a smartphone has more advanced communications capability than a police officer or a deputy carrying the radio. given the technology that is available and the complexity of the trip that we face, this is unacceptable. >> that is ray kelly testifying before the committee. the committee passed bipartisan support, a measure to set aside a block of radio frequencies for modelling the system. kay bailey hutchinson and democrat jay rockefeller. >> the fact that we have waited this long is stunning enough. but we started this sometime ago, there isn't a single first responder organization in the country, not a single governor, not a single mayor, not a single magistrate, not a single -- everybody supports it. everybody supports it. >> on the house side, it's auctioned off for money to carriers than giving it to first responders. they say giving it away is a missed opportunity to reduce the deficit. no unified modern system. things are better for first responders here in new york and wherever the next disaster may strike. but they're nowhere near as good as it could be or their surviving comrades tell it are they as good as the american finest and bravest deserve. this chief testified to congress about the communications problem. what's the hold up. there were some members on the house side that feel that. >> explain what the spectrum would do for the first responders. >> it's available in the new technology. commissioner talked about a 16-year-old having more capabilities than we do today. it gives us the ability to do data, voice, all kinds of capabilities we don't have today. we're on two-way voice communications. >> firefighters go to the building, they could pull up schematics of the building on a hand held device? >> this net work would be public safety built and built to our requirements and specifications and dedicated to us. we can't use commercial networks because during the earthquake, those systems get inundated, flooded with calls. they're no good for public safety use. with ems workers, this could benefit them. the scene of the incident to a hospital directly in realtime so doctors could triage. they could decide which patient needed to be treated and transported first. >> new york city, the police department, what do you now have? you have some level of the spectrum? >> what we're using right now is spectrum assigned to us decades ago. we have a very reliable, very robust two-way voice communications system. from a data perspective, we're nowhere. we need the new system and the spectrum to build it on so we can be not only capable of doing it here, but any place any first responder goes in the country, their device would be recognized and function. right now at washington and boston, our communications equipment will not work. >> it's not as if that doesn't happen. we've seen on big disasters folks coming all around in hurricane katrina. search and rescue crews coming from katrina and oh states. >> the nypd down there and people came down here on 9/11 from as far away from south carolina and maine. >> if this passes in congress, how long would it take to get up and running, functional. >> the technology is there now. it's a matter of building it. i would say within two years, we could have dysfunctioning in a lot of the areas in the this country. >> you're hoping to get the folks in congress do act? >> we need that. and folks need to understand they need to talk to their members of congress and tell them this spectrum should not be auctioned if it's assigned to public safety to save lives. >> being here, what's it like for you? >> we did a site inspection here a month ago. it brings back a lot of memories. it's tough to be here. and, you know, sunday being the tenth anniversary to have not fixed this problem to the point where we know we can fix it is -- is disturbing. >> thanks for being with us. >> thank you. >> good luck to you. up next, we're going to update our breaking news. new details about the possible new terror plot against the united states on the anniversary of 9/11. authorities telling cnn tonight they have a partial ideantity o one of the three people involved and they believe he's in the united states right now. we're going to be joined ahead. a disturbing report out of syria that could signal a new level of brutality in the government's program. we know they kill children, women, unarmed protesters. witnesses saying security forces barge into a hospital, took 18 wounded patients, some of them were in the operating room on oxygen, on life support. a doctor who witnessed the attack speaks out coming up. 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[ professor ] good morning students. today, we're gonna... welcome back to ground zero on this beautiful night. you're looking at the north reflecting pool, one of two pools. the design is called reflecting absence. the new information about the terror threat. authorities are working to try to unravel. this moment, they told cnn they have the partial identity of one of the three people believed involved and they believe that person is currently in united states tonight. all over new york and washington, heightened security, check point, roadblocks, seen that all day long. police pulling over trucks and vans looking for explosives. the plot is thought to involve a car or truck bomb. officials can't rule out other means. tonight the police and assault rifles are in the train stations and many people in both cities are more on edge or at least asking more questions. assistant director tom fuentes joins me now along with susan candiotti. we heard from fran townsend earlier in the program. he believes that authorities believe one suspect is already in the united states. officials have announced a name. this is basically a man hunt going on right now? >> exactly, anderson. but the reporting is that it's a very common name and very difficult for the authorities to actually find the person, specifically identify him and track him down. >> were -- the -- the sourcing on this day is that it's only a partial identity. what does that mean? >> well, obviously, the first name or the last name and a very common name in the united states. so, it again makes it difficult. my understanding is that the sourcing of the information coming from pakistan also has been commonly intercept in the past and that's why they think it's credible information, but, again, they're putting the fact that the information coming in because it's this weekend, has heightened the alert even more. >> susan, is there any sense or any authorities possibly figuring out a name or a partial name, or maybe would that cause more problems given that it's a common name? >> they're worried about that, anderson. worried about too much information getting out that they think possibly impairs them to track people down. they are concerned about too much information, too many leaks. but certainly, they are shaking the bushels. they're going to people that they talked to before, that they were talking to even before this threat became known. they're hearing the same chatter that we're hearing about now that possibly oversees who might be responsible for this. but possibly al qaeda's number two man. so many leads to track down. but i'm also hearing this, that it's entirely possible with the very credible information, if it weren't for 9/11, it's possible that the public wouldn't have heard about it, but because of the proximity of the 9/11 anniversary, they had to get the word out and make sure people were on their guard. >> it's interesting in new york today to walk or bike around as i was and to see the grid lock as a result of the vehicle check points, we haven't seen that level of overt security quite a whil while. how effective are check points like this. is it more -- is it more effective or is it more for sort of peace of mind? >> the interesting thing is we may never know. if the attack doesn't happen, we may never know somebody saw all of that activity on the part of the police and decided they couldn't do it. but the entire city became too hard of a target. but on the other hand, some of the earlier attack plans that occurred, for instance, the time square bomber in new york city, he wants to pakistan, received training on how to use propane tanks that are more commonly available that doesn't alert authorities. he didn't properly set up the tanks and they just sat there and smoldered until they attracted public attention and alerted police. that's the problem we don't know. the fewer the people involve in the attack plan, the more primitive the methodology they're going to use. in other words, the more commonly available the ingredients are, it's only that much more difficult to do it. and especially you have -- they were approaching with the tripline. now you have the plot in the last year where the individual was going to obtain chemicals, make a bomb, and blow up george bush's home in dallas, texas. the chemical company called the police and the fbi. they had a plot this past week in germany where a palestinian and lebanese individual tried to obtain chemicals to make a bomb and that chemical company called the german police. so you have the more interest, the more public awareness that's been raised, the more difficulty they're going to have in being able to wage the kind of attack that would do the most damage. but as i said, it becomes more primiti primitive, it involves fewer people. it becomes easier to conduct. >> tom fuentes. thank you very much. sus susan henderson has an update. >> 18 wounded patients, just took them out. five of the patients were reportedly removed from an operating room, including two who were described as unconscious. that was according to human rights watch. we spoke to the doctor who said he can't reveal his name. it's simply too dangerous. >> the most terrible moment when you can't when your mission is to protect people and he has prevented you from getting help to those -- to the patients. i don't know what happened to them. but -- >> in libya, there's been fighting on the streets with the deadline coming and going for gadhafi loyalives peacefully surrender with no deal. clashes took place in egypt. protesters got in to the building at the embassy, tossed papers out of the window on to the street. one man died of a heart attack and two others were injured in a clash between protesters and the police. the protesters want the israeli ambassador to leave egypt. this is one of several political protests today. stocks took a beating today due to fears over europe's financial woes. fuelling the selloffs, the resignation of an executive board member of the european central bank. the dow sank 304 points today. the nasdaq fell 71. the s&p dropped 32 points. anderson, back to you. here's piers morgan on what's coming up on "piers morgan on the." new york under a new terror alert. two stories of survival. cantor fitzgerald, 658 employees were lost on that terrible day. no one in that north tower made it back alive. in the ten years since, howard ludwig rebuilt the firm and his life and he tells his emotional story in a few moments. and nora manning on the way to her office when the