The changes include injecting CIA analysts into the FBI, according to Rep. Porter Goss, chairman of the House Intelligence Committee.
"I know the (FBI) director has personally tried to do some reorganization. We're going to hear a lot more about that in the days ahead," Goss told "Fox News Sunday."
FBI Director Robert Mueller has already briefed lawmakers on the reorganization plan, Senate Republican leader Trent Lott said on CBS's "Face the Nation."
An FBI spokesman confirmed some changes were in the works at the bureau, which is traditionally charged with domestic law enforcement duties, and said only an announcement would be made "in the near future." The CIA is responsible for intelligence-gathering overseas.
"Director Mueller has testified before that the FBI will be undergoing some reorganization, and those plans have not yet been announced," FBI spokesman Steven Berry
Also Sunday, Goss said he will examine whether concern the FBI would appear to be using "racial profiling" led it to remove key details from a search warrant whose rejection kept the FBI from learning more about a terrorism suspect before Sept. 11.
Goss said on CBS' "Face the Nation" that the handling of the Minneapolis FBI office's application for a warrant to search Zacarias Moussaoui's computer troubled him.
"Because that basically is hampering an investigative tool which we need very badly right now," said Goss, R-Fla.
The Minneapolis office, after arresting Moussaoui at a Minnesota flight school last August, was concerned that he was seeking to hurt Americans and wanted to gather more information.
Goss, whose committee is joining with its Senate counterpart to investigate what the government knew and did to fight terrorism before the Sept. 11 attacks, referred to a letter Minneapolis FBI counsel Coleen Rowley wrote May 21 to FBI Director Robert Mueller about the Moussaoui case.
The letter alleged that terrorism supervisors at FBI headquarters rewrote the Minnesota office's warrant applications and affidavit and removed key information about Moussaoui before sending them to a legal office that then rejected the paperwork as insufficient.
Rowley wrote that some of the revisions "downplayed" the significance of intelligence linking Moussaoui to Islamic extremists, and blamed the changes on a flawed communication process.
Goss said problems with the warrant application worried him most, adding that if the letter is accurate, "that people were reluctant — there was a culture in Washington that said, `No, we don't want to rock the boat. We want to — we're too worried about profiling, those kind of things.' We've got to know about that and figure out as a society how we are going to react."
Asked if he meant one reason the FBI may have rejected a warrant request was concern about racial profiling, the Florida Republican replied: "I don't know the answer to that. But I'm surely going to ask the question, because it has been suggested."
The FBI declined to comment.
Goss' remarks came as Senate Majority Leader Tom Daschle continued to press for an independent commission to investigate intelligence failures leading up to the September attacks.
Daschle, D-S.D., said President Bush asked him on Jan. 28 not to seek an outside commission. He said previously that Vice President Cheney made a similar request Jan. 24.
"They were concerned about the diversion of resources," Daschle said on NBC's "Meet the Press," adding that the request was repeated on other dates.
Bush and Cheney said last week that Congress' intelligence committees — which can keep secret the classified information supplied by the administration — are the proper panels for an investigation.
Bush national security adviser Condoleezza Rice reinforced that position Sunday, saying the administration worries "about anything that would take place outside of the intelligence committees."
"I think the important thing here is for everybody to take a deep breath and recognize that we still have a very important and indeed dangerous war against terrorism under way," she said on "Fox News Sunday."
Rice said ongoing FBI investigations shouldn't be jeopardized by information "spread to the first pages of the newspapers."
The first House-Senate intelligence committee hearing into the attacks will take place on June 4, but will be closed to the public since classified information will be discussed.
FBI Director Mueller, meanwhile, is preparing to announce an overhaul of the agency to better fight terrorism. He plans to create a new team in Washington to centralize terrorism fighting and ensure all intelligence is evaluated thoroughly, officials have said.
CIA spokesman Bill Harlow said Sunday that more than two dozen CIA analysts and at least one senior manager from the agency's Directorate of Intelligence will assist Mueller's reorganization.
In addition, CIA analysts will be sent to several major U.S. cities to review FBI terrorism cases to look at information in the larger context of international terrorism, Harlow said.
"The FBI's focus in the past has been on fighting crime. Analysts at the CIA have probably got a broader experience in dealing with international terrorism," he said, adding that everyone is in favor of improved communication between the agencies.
Goss, speaking earlier on Fox, said he thinks the FBI at this point isn't capable of doing the intelligence work needed to fight domestic terrorism.
"I think they've got to go through a big learning curve, a lot of readjustment," Goss said.