After the 2nd explosion is when the sh*t really hit the fan. Most of the workers were out and vails gate and city of Newburgh firefighters were doing an interior search and attack. At that time, everyone was there or were on the way, state firefighters from Stewart, DEC, etc. heard even homeland security, FBI was there.
I had a feeling this would have happened there sooner or later. Just passing the building you could smell the nail polish fumes in the air. A real sweatshop IMO.
edit. They found the body of the missing man inside the building.