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".
United Airlines Flight 175
United Airlines Flight 175 was a scheduled domestic passenger flight from Logan International Airport, in Boston, Massachusetts, to Los Angeles International Airport, in Los Angeles, California. On September 11, 2001, the Boeing 767-200 operating the route was hijacked by five al-Qaeda terrorists and was deliberately crashed into the South Tower of the World Trade Center in New York City, killing all 65 people aboard and an unconfirmed number in the building's impact zone. The attempt was part of the September 11 attacks.