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.
PENTTBOM
The investigators were quickly able to link the 19 men to the terrorist organization al Qaeda, by accessing their intelligence agency files. The "New York Times" reported on September 12 that: "Authorities said they had also identified accomplices in several cities who had helped plan and execute Tuesday's attacks. Officials said they knew who these people were and important biographical details about many of them. They prepared biographies of each identified member of the hijack teams, and began tracing the recent movements of the men." FBI agents in Florida investigating the hijackers quickly "descended on flight schools, neighborhoods and restaurants in pursuit of leads." At one flight school, "students said investigators were there within hours of Tuesday's attacks." "The Washington Post" later reported that "In the hours after Tuesday's bombings, investigators searched their files on [Satam] Al Suqami and [Ahmed] Alghamdi, noted the pair's ties to [Nabil] al-Marabh and launched a hunt for him."