World Trade Center Health Program
On September 11, 2001, 19 terrorists associated with the Islamist militant group al-Qaeda hijacked four passenger jets in a series of suicide attacks on the United States, killing 2,996 people and injuring more than 6,000 others. Hijackers flew planes into two main towers of the World Trade Center, resulting in the collapse of three buildings of the World Trade Center complex, and the Pentagon, resulting in the partial destruction of the western side in the building. The resulting dust cloud due to the collapse of the World Trade Center covered Manhattan for days and contained thousands of tons of toxic debris, including asbestos and other known carcinogens. Another hijacked plane crashed into a field in Shanksville, Pennsylvania following an attempt by the passengers to retake control of the plane. No one in the airliners survived.
As of 2011, approximately 18,000 people have received medical treatment for illnesses related to toxic dust from the World Trade Center site. A study of rescue workers released in April 2010 found that all those studied had impaired lung functions, and that 30–40% were reporting little or no improvement in persistent symptoms that started within the first year of the attack. In 2011 a major research study showed significant long term medical and psychological effects among first responders to the World Trade Center site. These effects include elevated levels of asthma, sinusitis, Gastroesophageal reflux disease and posttraumatic stress disorder.
September 11 attacks advance-knowledge conspiracy theories
On December 22, 2010, a United States Federal Judge signed a default judgment holding Iran, the Taliban and al-Qaeda liable following an open court hearing in which the evidence was produced by the plaintiffs' attorneys which they said showed that Iran assisted the hijackers. 9/11 commission members and witnesses who claimed they were Iranian defectors and members of Ministry of Intelligence and National Security and the Iranian Revolutionary Guards also testified during the hearing. The suit "Havlish, et al. v. bin Laden, et al" was brought in 2001 by Fiona Havlish whose husband died in the North Tower. Abolghasem Mesbahi, who claimed he was a former Ministry of Intelligence operative in charge of Iran's espionage operations in Western Europe testified that he was part of a task force that designed contingency plans for unconventional warfare against the United States code-named "Shaitan dar Atash"/"Satan in Flames" which included crashing hijacked passenger airliners into the World Trade Center, the Pentagon, and the White House, and that in the summer of 2001 he received three coded messages telling him to activate the plan. An Iranian government memorandum was presented as evidence that Iran's Supreme Leader Ayatollah Khamenei had pre knowledge of the attacks. Several days after the ruling a spokesperson for Iran's Foreign ministry said charges that Iran "had a hand in planning the attacks and that one of al-Qaeda's members was present inside the country is baseless" and said "With the repetition of such claims to back its political aims the U.S. is putting the peace and security of the world in jeopardy,".