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".
King Fahad Mosque (Culver City, California)
According to FBI documents and a CIA memo noted in a congressional report into the attacks of September 11, 2001, the hijackers Khalid al-Midhar and Nawaf al-Hazmi may have been in contact with Saudi diplomat Shaykh al-Thumairy, who was the chief imam at the King Fahad Mosque (most of the 9/11 hijackers were Saudi nationals and several were not fluent in English and had little experience living in the West). According to the congressional report, the mosque was identified by the FBI as a site of “extremist-related activity both before and after September 11”. According top the commission, “several subjects of FBI investigations prior to September 11 had close connections to the mosque and are believed to have laundered money through this mosque to nonprofit organizations overseas affiliated with Usama Bin Ladin.”