Washington (CNN) The Justice Department informed lawmakers Thursday that the report from its internal watchdog on the FBI's handling of the Hillary Clinton email investigation will reveal additional private text messages exchanged between two FBI officials who have come under scrutiny for their unfiltered criticism of then-presidential candidate Donald Trump, according to a department spokesperson.

The news of new text messages between former FBI lawyer Lisa Page and FBI counterintelligence agent Peter Strzok came just hours before Justice Department Inspector General Michael Horowitz will issue an exhaustive new report on the FBI's actions leading up to the 2016 election. Page and Strzok both worked closely on the investigation and Horowitz is expected to address the new messages in his report, but the Justice Department did not reveal their contents in the letter to Congress.

Thousands of messages have been turned over to Capitol Hill over the last several months, but the latest batch was only recently uncovered by Horowitz's office.

Previous batches of texts between Page and Strzok offer a private glimpse into an extra-marital affair, internal office politics, preparation for congressional hearings, mocking a variety of politicians during presidential debates and the fallout from the surprise firing of FBI Director James Comey.

Trump and members of Congress have used the messages to fuel unsupported conspiracy theories, but the private exchanges also leave little doubt about Page's and Strzok's unadulterated contempt for Trump. Whether their political views influenced the substance of their work is a topic of Horowitz's report.

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