The now-infamous warning to then-President Bill Clinton was tucked at the bottom of a presidential intelligence brief delivered on September 10, 1998: A group associated with al-Qaeda leader Osama bin Laden "may fly an explosive-packed airplane into a US city".

CIA declassifies presidential briefings that trace al-Qaeda threats to hijack plans and target US cities before 9/11

A September 10, 1998 brief — parts of which have been redacted — says that Al-Qaeda “may fly an explosive-packed aeroplane into a US city”.