One pic (left) appears to have been taken IMMEDIATELY after bomb dropped, showing heavy black smoke while the other pic (right) appears to have been taken seconds/minutes later as the smoke was rising in various areas within the same site; black smoke was changing to grey.
It's obvious that no one commenting on this here has any graphics arts experience or ever used a "clone" tool.
It would be so easy to do it right. Take a second picture and apply some more smoke from that one without repeating those little curlique in the picture. If you use a clone tool and clone the same pattern over in the same pic and over and you're begging for discovery.