Perfect controlled demolition of twin chimneys - video

[IAMSatisfied]

Wondering what was the flash of lights running up the extreme right side of the building at 0:14 seconds. They did not look like explosions, seemed to be in the windows.

They're interior explosions... if you scroll through the video frame by frame at that point you can see the flame spread.

For those who may not know, you can scroll through a youtube video frame by frame by using your < & > keys while the video is paused.