Shocking photos capturing the moment when the building collapses with "9.11" that had never been released before

There were various pictures and images of the terrorist attack on the United States in September 11, 2001, so-called "9.11" until now, too much shocking photos and the like have not been released yet, it is released this time The picture is also one of such shocking photos.

Details are as below.
New World Trade Center 9/11 aerial images from ABC News | Mail Online

These photographs were taken by a helicopter of the New York City Police Department, and it was taken of the moment WTC collapsed.









Why is it released at this time? Immediately after 9.11National Institute of Standards and TechnologyWas collecting these pictures from a number of amateur photographers and studying it, but its research ended in 2005, the American broadcasting station "ABC"FOIARequested to be disclosed by, and realized. There are 2779 undisclosed photos on 9 CDs in all, and this time the picture is supposed to be some of them.