WASHINGTON – The CIA was alerted to Zacarias Moussaoui in April 2001 by an informant who knew the Frenchman only by an alias and the agency didn't link the two names until well after Sept. 11, government officials say.
As a result, the CIA's original background check on Moussaoui — now charged as an accomplice with the hijackers — came up empty after he was arrested at a Minnesota flight school a month before the suicide attacks, the officials said.
U.S. investigators never heard of Moussaoui under his true name before Aug. 15, one intelligence official told The Associated Press, speaking only on condition of anonymity.
That official said that in April 2001 a CIA informant mentioned a man by a different name that he had met in 1997 during a gathering of Islamic extremists.
The source reported he learned little else about the man, and a CIA trace on the name turned up nothing more, the official said.
CIA first learned there was a connection in early 2002 when the agency learned that the source recognized Moussaoui from pictures he had seen on television, the official said.
Officials familiar with the intelligence said the alias provided by the informant was somewhat similar to one of the aliases listed for Moussaoui in his December 2001 indictment — Abu Khalid al Sahrawi.
One official said the alias provided by the intelligence source was similar to Abu Khalid, but that the rest of the name was different. The official declined to provide the full name or be more specific.
Terrorists and foreign criminals frequently use multiple names and aliases to make tracking them harder.
House and Senate intelligence committee members on Tuesday begin hearing evidence in secret about the full extent of information the FBI, CIA and other U.S. agencies possessed about the hijackers before Sept. 11.
Agencies have acknowledged lapses in information gathering and sharing but have said none of their prior information pointed directly to the hijacking plot.
Intelligence experts say the pre-Sept. 11 intelligence about Moussaoui would only have been useful if linked to one of the names the government knew him by.
Otherwise, it would not stand out among the hundreds of bits of information that arrive about individuals each day, they said.
"Even if they had gotten onto Moussaoui and connected him to the alias provided by the earlier source, the best they could have done was prevented Moussaoui from coming into the United States," former CIA counterterrorism expert Vincent Cannistraro said.
Cannistraro said the Al Qaeda network would have others ready to enter the country if that happened. He said the real challenge for the congressional review is to determine ``how do you better sort out the wheat from the chaff'' in raw intelligence.
Former CIA Deputy Director John Gannon said terrorism intelligence is among the most fragmentary of all reports received by CIA.
Gannon said one lesson of Sept. 11 is that U.S. intelligence officials need to rely more on technology, which has been traditionally distrusted for fear it could divulge methods or sources, to help find overlooked clues.
"I can understand why an individual might miss information. But I don't understand why we don't have electronic processes that ensure information gets cross checked as many times as possible," he said.
After the name check on Moussaoui came up empty last August, CIA officials put out a routine information request to cooperating foreign intelligence services.
Within a short period of time, it received information from France that Moussaoui was a known Islamic extremist, officials said.
Among the information the French provided was an interview their agents conducted with Moussaoui's brother. Officials said the FBI discounted the interview to some degree because the brother acknowledged he had not seen Moussaoui for several years.