She said that bureau personnel might be furloughed and that vocational education programs and others might be curtailed.
F.B.I. documents reviewed by The New York Times show that bureau scientists focused on tin early in their eight-year investigation, calling it an "element of interest" and a potentially critical clue to the criminal case.
Ms. Clemente filed a Freedom of Information Act request for Mr. Scarpa's file in April, and the F.B.I. acknowledged her request in a letter on June 9, saying that bureau officials would search their records for relevant papers.
She also warned Mr. Mueller that he should stop saying publicly that bureau investigators possessed no information that could have led to uncovering the terrorist plans for Sept. 11.
Officials confirmed an account in Newsweek magazine that bureau agents in Minnesota had requested a warrant to review his computer hard drive but that they had been turned down by Justice Department officials in Washington.
They said that bureau security procedures had been lax and that the computer system used by most agents was so old it could not store graphs, charts or even photographs of suspects.
