http://www.cnn.com/2005/WORLD/meast/12/09/plane.terror.reuters.reut/index.html

The United States told Saudi Arabia more than three years before the September 11 attacks that Osama bin Laden might be targeting civilian airplanes, according to a newly declassified State Department cable.

The June 1998 cable, obtained by George Washington University's National Security Archive under the Freedom of Information Act, said the United States had no specific information that al Qaeda was planning such an attack, and did not say it might fly planes into buildings.

A copy of the cable, first reported by The New York Times on Friday, was obtained by Reuters. Fifteen of the 19 hijackers on September 11, 2001, were Saudi nationals.

The cable, from the U.S. Embassy in Riyadh to U.S. government officials, said concerns were based on threats bin Laden had recently made against military aircraft in an interview with U.S. network ABC.

"We could not rule out that a terrorist might take the course of least resistance and turn to a civilian target," the cable said, noting bin Laden had said his group did not differentiate between civilians and the military.
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The cable is the latest of several signs made public that U.S. officials had concerns, long before the 2001 hijacked airplane attacks on New York and Washington, that al Qaeda might be targeting aircraft.

Others include a highly classified President's Daily Brief report to former President Bill Clinton dated December 4, 1998, which was titled "Bin Ladin Preparing to Hijack US Aircraft and Other Attacks."