Building #7 was badly damaged when the north tower rained debris on it and the uncontrolled fires took it down. It fell from the inside first before the outside followed. Here's a firefighter, who was right there, predicting it would come down...
"See the way the smoke is? You see this thing is leaning like this? It's definitely coming down. There's no way to stop it. Because you have to go up in there to put it out and it's already... the structural integrity is not there in the building."
And for those who for years cited buildings don't collapse from fire as evidence to a controlled demolition...