Shooting death of Michael Brown is met with outrage and calls for his resignation. Wolf blitzer is off today. Im brianna keilar. Youre in the situation room. Following breaking news, a u. S. Government source telling cnn that officials now believe some senior members of a specialized terror cell survived an air strike this week in syria. The u. S. Abruptly attacked this group called khorasan, in an effort to disrupt the terror plot the u. S. Described as imminent. Also following an extraordinary battle that unfolded live here on cnn between isis militants and Kurdish Forces trying to keep the terrorists from seizing a town near the syrian Turkish Border. We are covering all angles of the breaking news with our correspondentings and our guests this hour. We begin with the latest, with cnn senior White House Correspondent jim acosta. What are you hearing at the white house, jim . Reporter i can tell you the white house is seeing positive signs in the fight against isis. But Top Administration officials remain deeply worried about the threat posed by another terror group, khorasan. After assessing this weeks air strikes in syria, u. S. Officials tell cnns evan perez they believe some of the Senior Leaders of the al qaedarelated group khorasan managed to survive and could still be plotting attacks. Top Administration Officials say khorasan may present a greater threat than isis. We have seen Khorasan Group as a determined, capable adversary who presented a clear and present danger. And there has been talk this week about the reason for the air strikes was to disrupt a, some described it as an imminent attack. Reporter unlike the battle against isis, the u. S. Mission against khorasan has been cloaked in secrecy, an approach the white house defended. Should this administration have been warning the public . In order to do that effectively, it does require us to be less than transparent. In terms of the activities that we are engaged in to mitigate the threat that they pose. Reporter but the white house is confident there is nothing to the threat raised by iraqi Prime MinisterHaider Al Abadi who said he new of an isis plot to attack u. S. Subways. Personally, i dont have any information about this. Reporter by contrast, the Obama Administration is trying to portray on image of clarity on isis. Still joint chiefs chairman Martin Dempsey is standing by his recent statement that he will recommend u. S. Ground troops in iraq if necessary, something the president has flatly ruled out. I stand by the statement. I will make a recommendation the president gave me a mission, destroy isil. And i will recommend to him what it takes to destroy isil. Reporter white house officials maintain that core Al Qaeda Leaders have been killed. But aides to the president insist he is as determined as ever to hunt all of them down. Jim, thank you so much. Lets get more now upon that extraordinary battle between isis and Kurdish Forces that cnn captured live. Cnns phil black is along the syrian Turkish Border. Phil, you saw it all unfold. Night has now fallen where you are. Whats the latest . Reporter brianna, here since the darkness has fallen, it has become progressively more quiet. The battle we saw being played out just across the Syrian Border from where were standing, that was very different during the afternoon here. What we witnessed was really an extraordinary scene. We saw a group of isis fighters attempting to advance through this Northern Region of syria, this region that is very much under the control and largely populated by ethnic kurdish people. And it was ethnic kurdish fighters that were putting up a very strong, very effective defense against these isis fighters. The isis fighters were effectively pinned down on the top of a hill, a ridgeline that we could see clearly from our position just here across on the other side of the border here in turkey. What we witnessed throughout the afternoon was both sides exchanging repeated small arms fire and heavier indirect fire as well, mortar rounds. The isis group was forced back over the course of the afternoon, pinned down, effectively, on a ridgeline. From there, our cameras saw them come under repeated far, even saw them take hits, casualties. Saw some of those people being taken away. And eventually as darkness began to fall, they decided to fall back behind the hill they were trying to advance beyond. Why this matters, why this is more than just some skirmish, extraordinary as it is to see live as we did, it is because these forces, these isis forces are trying to advance through this region from various directions towards a major town here, kobani. As they have advanced over the course of the week, they have really triggered a major humanitarian exodus from this region, refugees, hundreds of thousands, it is estimated, have made for the Turkish Border and crossed over. Firstly just because of the fear that the isis reputation brings with it. That reputation for brutality. These isis forces will continue to advance through this region. If they do that, that humanitarian crisis is expected to deteriorate. What the fighters, the local fighters on the ground and the refugees are telling us, what theyre asking us, really, is where the the International Coalition that is striking isis from the air in other parts of syria, what they would like to see is that sort of action here in this region of Northern Syria as these forces bear down on this kurdish town. Brianna . Amazing pictures, phil black. Stay safe while youre covering this story. The white house now is picking up some critical new support for the war against isis. Cnn Global Affairs correspondent elise labott covering this part of the story for us. Whats the latest . Reporter today, britain said it would join the air campaign in iraq along with several european nations. But when it comes to syria, for now the u. S. And their arab partners are on their own. The british Prime Minister was blunt, Warning Parliament the threat by isis was, quote, no fantasy and there was no walkonby alternative to join the u. S. Led military campaign. Left unchecked, we will face a terrorist caliphate on the shores of the mediterranean and bordering a nato member with a declared and proven determination to attack our country and our people. Reporter for seven hours, David Cameron fielded tough questions on the goals of air strikes in iraq. Its a civil war, a quagmire into which britain should tread softly what i can be clear about is having spoken to the kurdish leaders in iraq and having spoken to the iraqi Prime Minister, theyve both been frank that they want our help. Reporter in the end, lawmakers approved a limited deployment but only in iraq. Syria, it turns out, wasnt even on the table, designed to prevent the same embarrassing defeat the british Prime Minister suffered last year when parliament rejected his call to join u. S. Air strikes against syria, which casts doubt on britains reputation as americas closest ally during times of crisis. And other european nations are joining arab states in the Global Coalition against isis. French planes are already bombing isis targets in iraq. The netherlands says six f16 fighter jets will carry on air strikes and 250 troops will train iraq and Kurdish Forces. And denmark and belgium also announced plans to send fighter jets for the next phase of the air campaign. And the big question is where is turkey now that the 49 turkish diplomats being held by isis have been freed . They take part in the military campaign . The state Department Says military action isnt a litmus test for cooperation. They say turkeys done a lot to crack down on foreign fighters and will do more of that. Privately, u. S. Officials expect that turkey will play a military role and that officials are having discussions with the turkish government about just what that role will be. But they are very much at odds. Elise labott, thank you for that report. Lets get more on this with the Pentagon Press secretary, rear admiral john kirby. You just saw this dramatic report and these pictures that are coming from where the Kurdish Peshmerga fighters are really begging for help. Thats the question here, i think theyre wondering. I know the chairman of the joint chiefs of staff got at this a little bit but he also seemed to describe a situation where if the forces are separate, which they appear to be in this case, that this would be an ideal situation for conducting air strikes. So where are they . Well, were putting pressure on isil from the air inside syria. Weve done that all week. Most of the targets weve gone after have been strategic, trying to get at their ability to sustain themselves. Im not telegraphing future potential operations. But i can tell you the mandate to the u. S. Military is clear. Were going to keep pressure on them in iraq and in syria and thats going to persist for quite some time. It seems like one of the issues has to do with spotters. There arent really eyes on the ground in many of these situations. And weve heard officials talking about this. Is that the issue here and if thats the case, Public Opinion aside, should there be some u. S. Boots and eyes on the ground . The commander in chief has been clear. Theres not going to be u. S. Personnel, military personnel on the ground in a combat role, either in iraq or in syria. And you dont need spotters to conduct air strikes everywhere and in every circumstance. Sometimes its helpful. But you dont have to have them in every case. Weve done very effective strikes in syria without spotters on the ground. But you need ground forces, competent willing partners on the ground. But they should be indigenous partners. Thats why were supporting the Iraqi Security forces inside iraq. The report you just showed demonstrates that very much. Local fighters are probably the best able to know the ground and know how to defend their communities. I wont get ahead of strikes that may or may not occur. But i can tell you from the air, were going to continue to do what we need to do to put pressure on these guys. And obviously one of the issues is sort of vetting some of those certainly Syrian Rebels to see if they are good partners in all of this for the u. S. Admiral kirby, stick with us. Well have more. We have more to talk about, especially on this issue of the Khorasan Group, what one expert refers to as al qaeda allstars, after the break. She inspires you. No question about that. But your erectile dysfunction that could be a question of blood flow. Cialis tadalafil for daily use helps you be Ready Anytime the moments right. You can be more confident in your ability to be ready. And the same cialis is the only daily ed tablet approved to treat ed and symptoms of bph, like needing to go frequently or urgently. Tell your doctor about all your medical conditions and medicines, and ask if your heart is healthy enough for sex. Do not take cialis if you take nitrates for chest pain, as it may cause an unsafe drop in blood pressure. Do not drink alcohol in excess. 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Consider an aarp Medicare Supplement insurance plan. Go long. We are following this breaking news this hour, growing concern among u. S. Officials that Senior Leaders of an al qaeda cell plotting an imminent attack may have survived an air strike in syria this week. The Pentagon Press secretary rear admiral john kirby is back with us to talk about this. And we have evan perez, one of our reporters here at cnn, he is reporting that u. S. Officials believe that at least some of these senior Khorasan Group members, the folks who one of our experts has referred to as al qaeda allstars, that they survived this attack. Can you give us any more information about this . Im sorry. I thought you were going to him. No. Were still assessing the results of this strike. And we know that we hit the targets we were aiming at. We know that we hit some of the capabilities that they had on those sites. Certainly we had reason to believe that some of the leadership was present at those sites when the strikes occurred. But were still assessing and its difficult to do. Its going to take a little time to know what, if any, in terms of individuals were hit as a result of it. And so can you sort of explain something to me we just heard from jim acosta at the white house. He was reporting that white house officials are still saying that core al qaeda has been decimated. And yet khorasan is this al qaeda group, is very much in line with al qaeda. Its sort of an al qaeda offshoot. It is al qaeda, right . So is it true that you have core al qaeda having been decimated . We do believe weve decimated core al qaeda over the past 10, 12, 13 years, of course we have. And weve had a tremendous effect on them. That doesnt mean that there arent, as you described it, offshoots and splinter organizations that are affiliated, sometimes loosely, sometimes more tightly, with al qaeda. Theyre still out there and still wish us harm. The Khorasan Group is one of those groups. Small, very potent with lethal capabilities that they were trying to develop. Again, we felt this was a solid case to be made to hit these guys before they got into an execution phase of what could be a very dangerous attack on a western target. But, yes, of course theres still offshoots that can be very, very dangerous. I think this gets lost a little bit. Just because it may be a, quote, unquote, offshoot of al qaeda, theres a notion that theyre less capable or less dangerous or less important. We dont look at it that way. Certainly not. The abilities of this group are very clear that they are pretty advanced. Allstar al qaeda as one of our experts put it. We heard from secretary hagel and the chairman of the joint chiefs of staff. Secretary hagel saying air strikes are just the beginning. Martin dempsey saying there will obviously need to be Ground Troops. Doesnt have to be americans, others in the region. Who else is going to send in Ground Troops . We believe the most important ground force, particularly in this part of the world, are indigenous ground force, the people that live there, the people that have to defend their own citizens and their own communities. In iraq, its security forces. Up north, were working closely with the peshmerga as well. In syria, it will be the syrian moderate opposition. Were looking forward to Getting Started on this trainandequip program. But you want competent people in the region on the ground, people that know the territory and the politics and the culture. And you need that certainly to really capitalize on the air strikes to have these ground forces. How long is that vetting process going to take so that the pentagon is comfortable knowing who the Syrian Opposition members are that they can rely on . I think thats a great question and im glad for it. Its going to take some time. We think the recruiting and vetting process will take three to five months. And from there, eight to 12 months before trainees can go back into zishsyria, ready to g with leadership in place. Its going to take time. We want to do this right. More than we want to do it fast. Now that we have