World Trade Center site
On the morning of September 11, 2001, Islamic terrorists affiliated with Al-Qaeda hijacked American Airlines Flight 11 and United Airlines Flight 175, both which were en route to Los Angeles, and intentionally crashed them into the two main towers of the World Trade Center. The towers collapsed within two hours of the collisions. 2,606 people, including 2,192 civilians, 71 law enforcement officers, and 343 firefighters, who were in the towers and in the surrounding area died in the attacks, as well as 147 civilians and the 10 hijackers aboard the two airliners. After the collapse of the World Trade Center, hospital workers and law enforcement officers began referring to the World Trade Center site as "Ground Zero".
William Rodriguez
Rodriguez also claimed to have seen hijacker Mohand al-Shehri scoping out the building prior to the attacks, in June 2001. A "Daily News" article says he told the FBI and the 9/11 Commission that he recognized the man after a brief, chance encounter months prior to the terrorist attacks. "It is believed that American Airlines Flight 11 hijacker Mohamed Atta cased New York City targets, including the Diamond District, but Rodriguez may have given the 9/11 panel the first eyewitness testimony about a hijacker inside one of the towers before the terror strike.