"Abruptly, there was an ear-splitting noise. The south tower shook, seemed to list in one direction and them began to come down, imploding upon itself. "It looked like a demolition," said Andy Pollock. "It started exploding," said Ross Milanytch, 57, who works at nearby Chase Manhattan Bank. "It was about the 70th floor. And each second another floor exploded out for about eight floors, before the cloud obscured it all."
http://www.geocities.com/defendtheusa/page5.html "As more and more and more and more and more emergency vehicles descended on the World Trade Center, I hear a second explosion in WTC 2, then a loud, low-frequency rumble that precipitates the unthinkable -- a collapse of all the floors above the point of explosion. First the top surface, containing the helipad, tips sideways in full view. Then the upper floors fall straight down in a demolition-style implosion, taking all lower floors with it, even those below the point of the explosion. A dense, thick dust cloud rises up in its place, which rapidly pours through the warren of streets that cross lower Manhattan."
"I decide it's time to get my daughter, who was taken by the parents of a friend of hers to a small office building, six blocks farther from the WTC than my apartment. As I dress for survival: boots, flashlight, wet towels, swimming goggles, bicycle helmet, gloves, I hear another explosion followed by a now all-too familiar rumble that signaled the collapse of WTC 1, the first of the two towers to have been hit. I saw the iconic antenna on this building descend straight down in an implosion twinning the first."
http://www.planetary.org/html/society/advisors/sept11account.html"The team moved ahead. Scant minutes passed. Suddenly the hallway began to shudder as a terrible deafening roar swept over them. That's when Will saw the giant fireball explode in the street. That's when Sarge shouted, "Run! Run to the left!"
Seconds later the team's entire world began to crumble. It was precisely 9:59 a.m. The Trade Center's South Tower had just collapsed."
http://www.bowhunter.com/feature_articles/BN_FromTheRubble/"Official: Battalion 3 to dispatch, we've just had another explosion.
Official: Battalion 3 to dispatch, we've had additional explosion.
Dispatcher: Received battalion command. Additional explosion.
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