ambition for mass casualty attacks. we must recognize that however strong we are, and however much we reprepare, we in the uk face the same threat. >> now, david cameron convened a meeting of his security team here, and they were discussing whether to raise the national threat level from the current situation which is severe, and that is the second highest up to critical. they decided against doing that at this point, but you can imagine as information coming in and surveillance picking up with the security forces here in the uk, they won't hesitate to raise that threat level if an attack is imminent. alex? >> thank you, ron mott in london bureau regarding the gatwick scare there. and now, the security of level is being raised around the world, and now, we are joined by kristen dahlgren, and what security forces are taking steps