An FBI official allegedly altered a document relating to the 2016 surveillance of Trump’s campaign adviser Carter Page, and is now under criminal investigation, according to CNN.

Justice Department Inspector General Michael Horowitz turned over the evidence of the altered document to federal prosecutor John Durham, who was appointed earlier this year by Attorney General William Barr.

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The alteration of the document “were significant enough to have shifted the document’s meaning and came up during a part of Horwitz’s FISA review where details were classified, according to the sources.”

The FBI employee admitted to the alteration of a document.

CNN reported, “Some witnesses who have been interviewed in Horowitz’s investigation have said they expect the inspector general to find mistakes in the FBI’s handling of the FISA process, but that those mistakes do not undermine the premise for the FBI’s investigation.”

The CNN article noted, “The possibility of a substantive change to an investigative document is likely to fuel accusations from President Donald Trump and his allies that the FBI committed wrongdoing in its investigation of connections between Russian election meddling and the Trump campaign.”