According to a CIA Intelligence Report on August 24, 2001: “As of late August 2001, there were indications that an individual associated with Al-Qa’ida was considering mounting terrorist operations in the United States. [Redacted] No further information is currently available on the timing of possible attacks or on the alleged targets in the United States.”
– CIA, “Terrorism: Sanitized Version of Threat Report,” (CIA Intelligence Report), The Central Intelligence Agency’s 9/11 File:, The National Security Archive, Aug. 24, 2001