Washington (CNN) Then-FBI Director James Comey knew that a critical piece of information relating to the investigation into Hillary Clinton's email was fake -- created by Russian intelligence -- but he feared that if it became public it would undermine the probe and the Justice Department itself, according to multiple officials with knowledge of the process.

As a result, Comey acted unilaterally last summer to publicly declare the investigation over -- without consulting then-Attorney General Loretta Lynch -- while at the same time stating that Clinton had been "extremely careless" in her handling of classified information. His press conference caused a firestorm of controversy and drew criticism from both Democrats and Republicans.

Comey's actions based on what he knew was Russian disinformation offer a stark example of the way Russian interference impacted the decisions of the highest-level US officials during the 2016 campaign.

The Washington Post reported Wednesday that this Russian intelligence was unreliable. US officials now tell CNN that Comey and FBI officials actually knew early on that this intelligence was indeed false.

In fact, acting FBI Director Andrew McCabe went to Capitol Hill Thursday to push back on the notion that the FBI was duped, according to a source familiar with a meeting McCabe had with members of the Senate intelligence committee.

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