U.S. intelligence officials warned President Bush weeks before the Sept. 11 attacks that Osama bin Laden's terrorist network might hijack American planes, but White House officials stressed the threat was not specific.
A White House official acknowledged to ABCNEWS that the information prompted administration officials to issue a private warning to transportation department and national security agencies weeks before the attacks. But, the official said the threat of a hijacking by bin Laden's al Qaeda organization was general in nature, did not mention a specific time or place and was similar to the variety of different terrorist threats U.S. intelligence monitors frequently.
"There has been long-standing speculation, shared with the president, about the potential of hijackings in the traditional sense," White House Press Secretary Ari Fleischer said. "We had general threats involving Osama bin Laden around the world and including in the United States."
Fleischer insisted that Bush did not ignore the threats, saying that hijacking warnings were something that past White Houses have faced for decades. No one, Fleischer said, could have conceptualized what happened on Sept. 11. White House officials believed the hijackings could occur in a more traditional manner.
Ignored Warning Signs
The revelation came as legislators demanded an explanation after an FBI memo alluding to ignored warning signs about Sept. 11 emerged. Two months before the hijackings, FBI agents in Phoenix reported their suspicions about Arab students at a Phoenix flight school, and directly referred to the possibility of a connection to bin Laden.
In a memo from the Phoenix FBI to headquarters, the agents recommended an urgent nationwide review of flight schools "for any information that supports Phoenix's suspicions" of a terrorist connection. The memo reportedly cited Osama bin Laden by name.
The memo's existence has apparently been known for months, but until recently, lawmakers and congressional staff have not gained full access to it, and the direct reference to bin Laden had not been revealed.
The memo has still has not been publicly released. Sens. Charles E. Grassley, Dianne Feinstein and Patrick Leahy are among the lawmakers asking the FBI to release it, and are demanding an investigation into the missed warning signs.
Not Until After 9-11
Illinois Sen. Dick Durbin, who has read the memo, told ABCNEWS today: "They raised a very serious terrorism concern and threat to the United States, and it involved the use of training at aviation schools and terrorists from the Middle East. That should have been fair warning."
The memo said terrorists might be seeking jobs with U.S. airlines or airports and urged FBI headquarters to "obtain visa information" on all "individuals obtaining visas to attend these types of schools" around the country.
None of that was done until after Sept. 11, after four hijacked airliners plowed into the World Trade Center, the Pentagon and a field in Pennsylvania. More than 3,000 people were killed and the World Trade Center was destroyed.
The mastermind was later identified as bin Laden.
Flight school owners in Phoenix, where alleged hijacker Hani Hanjour trained, say they had their own suspicions. "[If the FBI] were concerned, we would have been concerned and something would have happened. Investigations would have happened," said Richard Hastie, president of CRM Airline Training Center in Scottsdale, Ariz.
It was not the only signal FBI headquarters missed. Just weeks later, agents in Minnesota told headquarters of the arrest of suspected terrorist Zacarias Moussaoui at a flight school in St. Paul, suggesting he might be planning to hijack a plane and crash it into the World Trade Center.
FBI field agents wanted to search his computer but they were unable to get the authorization.
No one was able to put the two warnings — Moussaoui and Phoenix — together in the fateful weeks before Sept. 11.
"If you take Phoenix memo and the Moussaoui note, you've got the beginnings of a strong case that should have put the FBI on immediate alert.," said Alabama Sen. Richard Shelby, the ranking Republican on the Senate Intelligence Committee.
Moussaoui, a French citizen, is on trial in Virginia on charges based on the premise that he was to be the 20th hijacker on Sept. 11.
No Big Picture
The current FBI director, Robert Mueller, has told Congress none of the signals was sufficient to prevent the attacks, while conceding the bureau failed to properly follow them.
"We did not have the people who were looking at the broader picture to put the pieces in place," he said at a recent hearing.
The White House also insists the FBI did not drop the ball.
"The president agrees that information in that memo in and of itself would not have led to the prevention of the Sept. 11 attacks," Fleischer said today. "What took place was a sneak attack, an attack on our country while we were at a moment of peace."
The New York Times reported today that the Office of Intelligence within the FBI was formed as a direct result of this memorandum.
ABCNEWS' Brian Ross and Lisa Sylvester contributed to this report.