The State Department said Monday it is reviewing nearly 15,000 previously undisclosed emails recovered as part of the FBI’s now-closed investigation into the handling of sensitive information that flowed through Hillary Clinton’s private home server.

Lawyers for the department told U.S. District Court Judge James E. Boasberg on Monday that they anticipate processing and releasing the first batch of these new emails in mid-October, raising the prospect new messages sent or received by Democratic nominee could become public just before November’s presidential election. The judge is overseeing production of the emails as part of a federal public-records lawsuit filed by the conservative legal advocacy group Judicial Watch.

Representing the State Department, Justice Department lawyer Lisa Olson told Boasberg that officials do not yet know what portion of the emails is work-related rather than personal. Clinton, the Democratic nominee for president, served as secretary of state from 2009 to 2013. She has claimed that she deleted only personal emails prior to returning over 55,000 pages of her work-related messages to the State Department last year.

The State Department has publicly released most of those work-related emails, although some have been withheld because they contain information considered sensitive to national security.

Republicans are pressing to keep the issue of Clinton’s email use alive after the FBI closed its investigation last month without recommending criminal charges. GOP presidential nominee Donald Trump routinely criticizes Clinton for her handling of emails containing classified information.

Olson told the judge that State earlier this month received seven disks containing “tens of thousands” of emails Clinton sent or received during her tenure as the nation’s top diplomat. The first disk, labeled by the FBI as containing non-classified emails not previously disclosed by Clinton, contains about 14,900 documents, Olson said. The second disk is labeled as emails containing classified information.

Olson told Boasberg she could not immediately say how many emails are contained on the rest of the disks or how many might be copies of emails Clinton already has provided.

Given the large volume of messages, Olson said it was “extremely ambitious” for the agency to complete its review and begin releasing the first batches of emails to Judicial Watch by Oct. 14.

Judicial Watch lawyer Lauren Burke told Boasberg that the proposed schedule is too slow and pressed for faster release of the emails from the first disk. The judge ordered the department to focus its efforts on processing the emails from the first disk and to report back to him on its progress by Sept. 22.

As part of proceedings in a separate Judicial Watch lawsuit, a federal judge on Friday ordered Clinton to answer written questions from the group about why she chose to rely on a private server located in the basement of her New York home, rather than use a government email account.