I'm sure others have also commented on this, but what are the usual odds of survivors in a building collapse? Why aren't these rescuers looking for survivors, they are only looking for the dead. If it was a near-hit that brought the building down hours later, then you'd expect more survivors than with a direct hit, right? Have they been able to find survivors? I don't think survivors are in the script, because then the media would want to interview them, to get them to tell their experiences on the camera, and then too many people will deviate from the script and say something that doesn't add up, hence no survivors.
-PJ