The September 11 attacks (also referred to as 9/11) were a series of four coordinated terrorist attacks by the Islamic terrorist group al-Qaeda] against the United States on the morning of Tuesday, September 11, 2001. The attacks killed 2,996 people, injured over 6,000 others, and caused at least $10 billion in infrastructure and property damage. Additional people died of 9/11-related cancer and respiratory diseases in the months and years following the attacks. A good account of the attacks are at https://en.wikipedia.org/wiki/September_11_attacks.
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