The day the United States experienced the largest loss of human life by an act of terrorism in its history. Starting at 8:05 AM, the North Tower of the World Trade Center in lower Manhattan was struck by a hijacked airplane. Approximately 15 minutes later, the South Tower was hit. Eventually, both buildings collapsed, killing almost 2,800 people. Not long after, American Airlines flight 77 crashed into the Pentagon, killing 184 people. A fourth airplane, United Airlines flight 93, was also overtaken. Its intended target was the White House, but passengers attacked the hijackers and the plane crashed into a Pennsylvania field, killing all 40 aboard. The terrorist group Al-Qaeda, led by Osama Bin Laden, took credit for the attacks.