Have a look at this :
"1996-2001: Federal authorities have known for years that suspected terrorists with ties to bin Laden were receiving flight training at schools in the US and abroad. One convicted terrorist confessed that his planned role in a terror attack was to crash a plane into CIA headquarters.
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1998: An Oklahoma City FBI agent sends a memo warning that "large numbers of Middle Eastern males" are getting flight training and could be planning terrorist attacks. A separate CIA intelligence report asserts that Arab terrorists are planning to fly a bomb-laden aircraft into the WTC (World Trade Center).
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Sep 1999: A US intelligence report states bin Laden and Al-Qaeda terrorists could crash an aircraft into the Pentagon. The Bush administration claims not to have heard of this report until May 2002, though it was widely shared within the government.
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2000 – 2001: The military conducts exercises simulating what the White House says was unimaginable at the time: hijacked airliners used as weapons to crash into targets and cause mass casualties. One imagined target is the WTC. Another is the Pentagon.
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June 13, 2001: Egyptian President Mubarak through his intelligence services warns the US that bin Laden's Islamic terrorist network is threatening to kill Bush and other G8 leaders at their July economic summit meeting in Italy. The terrorists plan to use a plane stuffed with explosives.
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July 10, 2001: A Phoenix FBI agent sends a memorandum warning about Middle Eastern men taking flight lessons. He suspects bin Laden's followers and recommends a national program to check visas of suspicious flight-school students. The memo is sent to two FBI counter-terrorism offices, but no action is taken. Vice President Cheney says in May 2002 that he opposes releasing this memo to congressional leaders or to the media and public.
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Summer 2001: Intelligence officials know that al Qaeda both hopes to use planes as weapons and seeks to strike a violent blow within the US, despite government claims following 911 that the World Trade Center and Pentagon attacks came “like bolts from the blue.”
Summer 2001: Russian President Putin later says publicly that he ordered his intelligence agencies to alert the US of suicide pilots training for attacks on US targets.
Late summer 2001: Jordanian intelligence agents go to Washington to warn that a major attack is planned inside the US and that aircraft will be used. Christian Science Monitor calls the story "confidently authenticated" even though Jordan later backs away from it.
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Sep 11, 2001: In what the government describes as a bizarre coincidence, a US intelligence agency (the National Reconnaissance Office or NRO) was all set for an exercise at 9 AM on September 11th in which an aircraft would crash into one of its buildings near Washington, DC. Four wargames were also in progress at the time of the attacks. "
http://www.wanttoknow.info/911coverup10pg