The FBI provided the House Oversight Committee with documents relating to the FBI investigation into Clinton's email today, and committee officials are reviewing the information.
"The FBI has turned over a 'number of documents' related to their investigation of former Secretary Clinton's use of a personal email server. Committee staff is currently reviewing the information that is classified SECRET. There are no further details at this time," a committee spokesperson said.
The rare -- if not unprecedented -- move by the FBI comes after top House Republicans on Capitol Hill called for FBI Director James Comey to release the FBI's investigative file of the matter.
The FBI said in a statement today: “Consistent with our commitment to transparency with respect to the FBI’s investigation of former Secretary of State Clinton’s use of a personal email server, the FBI is providing certain relevant materials to appropriate congressional committees to assist them in their oversight responsibilities in this matter. The material contains classified and other sensitive information and is being provided with the expectation it will not be disseminated or disclosed without FBI concurrence.”
The material expected to go to the House Oversight Committee, the House Intelligence Committee, the House Judiciary Committee and the Senate Judiciary Committee.
Comey has vowed to be as responsive to lawmakers as possible.
An aide to Clinton said her campaign would prefer that the FBI materials be "released in-full" to the public, instead of released "piece-meal" in private to Congress so it can then be "released by people with motive" -- that is, Republican critics.
The documents that House members will be receiving are deemed classified, so access to them will be tightly controlled. The State Department had asked the FBI to review the documents before Congress received them.
The documents will not include any transcripts from FBI interviews in the case, as the FBI routinely does not transcribe such interviews. Similarly, Clinton was not under oath during her three-and-a-half-hour interview with the FBI, but that also is a common FBI practice during such interviews, and it is still a crime for witnesses not under oath to knowingly mislead law enforcement in the course of an investigation.
Testifying before lawmakers last month, Comey called Clinton's interview "the last step in a year-long investigation."
"The entire interview ... was focused on, 'So, what did you know, what did you see, what is this document,' that kind of thing," he told the House Oversight and Government Reform Committee.
Comey also said of the FBI: "We do not have a basis for concluding she lied to the FBI."
Even before the FBI planned to offer its investigative materials to Congress, Comey acknowledged that he is taking "unusual" steps in his handling of the Clinton email probe.
Many have questioned why he held a news conference on July 5 to lay out so much of the FBI's findings in a criminal investigation -- especially in an investigation in which no charges would be filed.
He later told lawmakers he was trying to "offer transparency to the American people" because "it was very, very important for their confidence in the system of justice."
"I care about the FBI's reputation. I care about the Justice Department. I care about the whole system deeply," he said. "And so I decided, I'm going to do something no director's ever done before. I'm not going to tell the attorney general or anybody else what I'm going to say or even [when] I'm going to say it."
He added, "I was very concerned that if I didn't show that transparency, that in that lack of transparency people would say, 'What is going on here? Something seems squirrely here.' So I said I would do something unprecedented, because I think it is an unprecedented situation."