September 11th, 2021

On September 11, 2001, terrorists hijacked four planes, piloting two of them into the World Trade Center’s twin towers in New York City and one into the Pentagon in Washington, DC. Passengers on the fourth plane attempted to overcome the hijackers, causing the plane to crash in western Pennsylvania instead of reaching its target in Washington, D.C. The twin towers at the WTC collapsed about an hour after being hit. More than 3,000 people died as a result of the attacks. The hijackers were agents of the Al Qaeda terrorist group led by Islamic extremist Osama bin Laden, who was headquartered in Afghanistan. In response, the US began unprecedented internal security measures and launched a war on terrorism with the support of many nations. 

* 2021 marks the 20-year anniversary of the terrorist attacks.

Source: www.history.com/9-11-anniversary