What caused the twin towers to collapse?

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Tags

1. #collapsing
2. #reasons
3. #result
4. #instance
5. #center
6. #remarkable
7. #fires
8. #building
9. #because
10. #office
11. #primarily
12. #collapse
13. #known
14. #first
15. #world
16. #uncontrolled
17. #contents
18. #fueled
19. #water
20. #trade
21. #along