Washington (CNN) The Justice Department will produce 500 pages of memos documenting what witnesses told special counsel Robert Mueller's office and the FBI during their investigation next month.

The documents, known as 302s, memorialize interviews conducted by the office and form the backbone of much of the Mueller report.

CNN and BuzzFeed News had sued for the documents under the Freedom of Information Act, and on Tuesday, a federal judge in Washington, DC, ordered the Justice Department to produce their first tranche of documents by November 1.

The 500 pages could shed new light on what key government cooperators like former national security adviser Michael Flynn and former White House counsel Don McGahn told federal investigators, but represents only a fraction of the underlying interview records that Mueller's office made: there were a total of 800 302 forms created by the special counsel's office, potentially numbering some 44,000 pages, Justice Department attorney Courtney Enlow said at a hearing Tuesday morning.

Enlow said the FBI had already begun to process the records but said a host of potential exemptions that had to be considered before their release, including national security implications, certain privileges, and exposure to ongoing prosecutions and investigations.

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