French Warned of Airline Plot Before 9/11

French intelligence agents learned in January 2001 that Al-Qaeda was planning to hijack US airlines and told the CIA chief in Paris, according to classified documents obtained by French newspaper Le Monde. Among the 328 documents was a note from January 2001 saying Al Qaeda had been plotting the hijack for months, though agents didn't appear to know that terrorists intended to crash the planes into buildings.

A former head of the French intelligence agency told the paper that the information didn't carry the same weight it would carry today, since hi-jackings at the time still consisted of someone taking over a plane with hostages and forcing it to land somewhere.