Late July 2001 (D): CBS later has a brief mention in a long story on another topic: "Just days after Atta return[s] to the US from Spain, Egyptian intelligence in Cairo says it received a report from one of its operatives in Afghanistan that 20 al-Qaeda members had slipped into the US and four of them had received flight training on Cessnas. To the Egyptians, pilots of small planes didn't sound terribly alarming, but they [pass] on the message to the CIA anyway, fully expecting Washington to request information. The request never [comes]." [CBS, 10/9/02] This appears to be one of several accurate Egyptian warnings based on informants (see June 13, 2001 and August 30, 2001). Could Egypt have known the names of some or all of the hijackers? Given FBI agent Ken Williams' memo about flight schools a short time before (see July 10, 2001), shouldn't the US have investigated this closely instead of completely ignoring it?