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".
International counter-terrorism activities of the CIA
On February 26, 1993, the World Trade Center was bombed. A group of the conspirators were arrested, convicted, and imprisoned. There has been no strong argument that al-Qaeda was involved, although there have been allegations, including by a former Director of Central Intelligence, that Iraq supported the operational cell. In a PBS interview in October 2001, former Clinton-era CIA Director James Woolsey argued a supposed link between Ramzi Youssef and the Iraqi intelligence services. He suggested the grand jury investigation turned up evidence pointing to Iraq that the Clinton Justice Department "brushed aside."