Potential leads went unpursued for years
An investigator found evidence that suggested Omar al-Bayoumi, a mysteriously well-connected Saudi student who knew two of the hijackers, might have had prior knowledge of the attacks, even though senior US officials had essentially exonerated him.
In a trove of seemingly disorganised evidence taken from al-Bayoumi's home in Birmingham, England, in 2001, [a] detective found a spiral notebook that contained a hand-drawn aviation diagram of a plane descending to strike a spot on the ground. An FBI agent who had studied aeronautical engineering concluded that the diagram showed a formula for an aerial descent like the one performed by Flight 77, the jet that Hazmi and Mihdhar hijacked, before it struck the Pentagon. Apparently, the notebook and its contents went unnoticed after al-Bayoumi's detention and hadn't been looked at again.
A former supervisor of the investigation said he thought the finding would have been more significant if it had been discovered in the fall of 2001.
"That would have been harder evidence," the supervisor, Joseph Foelsch, said. "If not a smoking gun, a warm gun."
Telephone records that were reanalysed years later revealed multiple calls among al-Bayoumi; Fahad al-Thumairy, a Saudi diplomat and imam; and Anwar al-Awlaki, a Yemeni American imam who was killed in a drone attack in 2011.
The CIA interfered with a planned FBI investigation, officials say
In 2010, the FBI planned to place two Saudi religious officials from the kingdom's Ministry of Islamic Affairs under full-time surveillance. The bureau had previously found that their travel overlapped with movements by the hijackers and people believed to be supporting them, and that they had ties to suspected militants. The two men sought new visas to study English in the United States, which officials feared could be cover for something nefarious.
But, FBI agents believe, the CIA intervened before the surveillance could happen.
The episode, which has not been previously reported, ended abruptly. In the Saudi capital of Riyadh, CIA officers objected strongly to the FBI plan, one former official said. "They didn't want to give the Saudis a black eye by letting these guys walk into a trap," the former official said. For reasons that remain unclear, the two Saudis canceled the visit at the last minute. FBI officials suspected that someone in the Saudi government had been warned.
A fabricated child
To gain the trust of a reluctant source, investigators lied and told a Saudi man he had a previously unknown child. The investigator employed a graphics editor to fabricate an image of a 5-year-old using images of the man and his wife.
"I knew I had a kid!" the man, Mohdar Abdullah, said excitedly.
The man later provided intelligence that led investigators to two more people who knew two of the hijackers when they were in California, helping to piece together where they spent their first two weeks in the United States.
Current status of the case
Federal prosecutors in New York issued grand jury subpoenas for two witnesses as recently as 2015, but the subpoenas were withdrawn after a senior prosecutor said there was not enough hard evidence for a successful prosecution.
In 2016, the investigative team was broken up, with the case assigned to another team. The Justice Department insists it remains open, but officials said there had been little activity since 2016.
Written by: Daniel Victor
Photographs by: Mark Weaver
© 2020 THE NEW YORK TIMES
