Updated

A senate committee has concluded that ignorance and ineptitude on the part of FBI supervisors and lawyers in Washington stopped field agents from following up on evidence that could have foretold the Sept. 11 attacks, according to a preliminary report obtained by The New York Times.

The report by the 19-member Senate Judiciary Committee will be made public next month. It focuses on errors in the case of Zacarias Moussaoui, who is charged in the Sept. 11 attacks, but points to a broader FBI culture that allowed the mistakes, The Times said.

When Minnesota agents arrested Moussaoui last summer they believed he was a terrorist who might use a commercial airplane as a weapon, so agents sought a search warrant under the 1978 Foreign Intelligence Surveillance Act.

FBI officials in Washington denied the request, apparently unaware that the federal act clearly permitted a warrant in that case, the report said.

When agents searched Moussaoui's computer after Sept. 11 they found information on commercial airplanes, crop dusting and a telephone number for a suspected al-Qaida member in Germany, officials said.

Also, an agent in Phoenix informed bureau supervisors in Washington of a threat from an unusual number of young Arab men seeking flight training in the U.S.

Senator Arlen Specter, a Republican member of the Committee and an author of the report, called the intelligence by field agents a "veritable blueprint of 9/11," The Times said.

The FBI had not seen the report and had no comment, but other law enforcement officials said FBI officials did not think they had the evidence to link Moussaoui to a terrorist group.

The report does not name bureau officials by name, but does single out titles, including those in the Radical Fundamentalist Unit.

Senate officials involved with the report are eager to have its findings made public after the Foreign Intelligence Surveillance Court harshly criticized the FBI last week for providing misleading information when seeking permission to use wiretaps and other surveillance techniques.

The court also criticized the Justice Department for seeking too much surveillance power after Sept. 11.

Senator Specter told the Times that the FBI had plenty of power before Sept. 11, but failed to use it properly.