. >> they linked him with michael the killer of the british soldier lee rigby as men who had been angeredause of their experiences a t the hands of british security. they say they can't talk about specific cases but they are always proportional to the threats. >> whether or not the security services did try to stop them from returning home from london they certainly seem to know who he was. the question, is how dangerous they thought he was because after all this appears to be a successful young man far removed from the stereotype of the isolated loser apparently at risk of radicalizing influences. >> looking at the profile of people, they are wellening gaited and they are socially mobile people. his parents apparently don't believe it is him but that's understandable. lawrence lee,le a al jazeera, in london. >> isil fighters have destroyed priceless antic witties from the ancient syrian era. the director that this isil video is genuine. some of the statutes that fighters are taking hammers hammers and drilled but four of the items are real. isil has recently destroyed several shrines in

. >> to add to it all, he was linked with the killer of the british soldier lee rigby as men angered because of their experiences at the hands of british security. they say they can't talk about specific cases but their efforts to maintain safety in the u.k. are always proportionate to the threats. >> whether or not the security services here did try to stop him from returning home to kuwait from london, they certainly seem to know who he was. the question is how dangerous they thought he was because after all this appears to be a successful young man far removed from the stereotype of the isolated loser apparently at risk of radicalizing influences. >> he's someone well educated, as well, and that chimes with a lot of the research done in terms of looking at profile of people who go to syria. overwhelmingly, they are well educated socially mobile people. these are not people coming from impoverished or deprived backgrounds. >> the media has made its mind up it is him but until he takes the hood off it won't be known for certain. his parents don't believe it's him, but that's underst

. >> reporter: to add to it all, he was linked to the killer of the british soldier, lee rigby as menangered because of their experiences at the hands of british security. they say they can't talk about specific cases, but their efforts to maintain safety in the u.k. are also proportionate to the threat. whether they tried to stop him from returning home to kuwait from london they certainly seemed to know who he was. the question is how dangerous they thought he was. because after all this appears to be a successful young man, far removed from the stereo type of the isolated loser apparently at risk of radicallizing influences. >> he was educated. and a lot of the research we have done in terms of the profile of people who go to syria, they are well educated socially mobile people. >> reporter: the media has by and large made its mind up that this is him. though when he takes his hood off, it won't be for certain. his parents don't believe it's him. but that's understandable. >>> david cameron has defended the country's security services while vowing to continue to fight against isil.

you remember the man who killed lee rigby on the streets of london. take a listen how they explained emwazi's background. >> he was such a beautiful young man. really. you know, it's hard to imagine the tra jekry. but it's not unfamiliar to us. once again, somebody that i met, came to me for help looking to change a situation in the system. when we are going to finally learn that when we treat people as if they're outsider, they will feel like outsiders and look for belonging elsewhere. our entire national security strategy for the last 13 years has only increased alien nation, only increased people feeling like they don't belong. >> and that is the caseworker at cage who dealt with mohammad emwazi and dealt with him for a number of years. he tried to go to kuwait unsuccessfully a number of times. he then tried to change his name and eventually managed to leave the country in late 2012 or early 2013. according to cage, security service came to his family's home and notified them that their son had traveled to syria. they believe that mi 5's alleged ha

. >> reporter: to add to it all he was with michael the killer of the british soldier lee rigby and angeredthe hands of british security and cannot talk about specific cases but efforts to maintain safety in the uk are always proportionate to threats and if the security services tried to stop him returning home to kuwait from london they seemed to know who he was. the question is how dangerous they thought he was because after all this appears to be a successful young man far removed from the stereotype of the isolated loser apparently at risk of radicalizing influences. >> well educated as well and that is in terms of research and looking at the profile of people who go to syria and they are well educated and socially mobile people and not people coming from impoverished or deprived backgrounds. and his parents don't believe it's him but that is understandable, lawrence in london. >>> head of public relations for al-qaeda convicted by a court in new york and faces life in prison for being involved in the u.s. embassy bombs in kenya and tanzia in 1998, 224 killed saudi arabia was one of bin

. >> reporter: to add to it all cage linked him with michael the killer of the british soldier lee rigbyed at the hands of british security and they say they cannot talk about specific cases but efforts to maintain security is regarding the threats. if they tried to stop mohammed emwazi from returning home to kuwait from london they seem to know who he was and the question is how dangerous they thought he was because after all this appears to be a successful young man far removed from the stereotype of the isolated loser apparently at risk after radicalizing influences. >> well educated and chimes with research we have done in terms of looking at the profile of people who go to syria and they are well educated and social mobile people these are not people coming from deprived backgrounds. >> reporter: the media has made its mind up this is mohammed emwazi, until he takes the hood off it won't be known for certain and his parents apparently don't believe it's him but that is understandable, lawrence lee, al jazeera in london. >>> a man described by prosecutors as one of al-qaeda early lea