Hillary Clinton’s campaign manager on Sunday was asked — and had no answer for — an email that surfaced on Friday in which an IT contractor who managed Clinton’s email server referred to the “Hillary cover-up operation.”

“This IT worker certainly sounded like he thought he was covering something up, no?” CNN’s Jake Tapper asked Robby Mook in an interview on “State of the Union.”

On Friday, the FBI released notes from interviews it conducted as part of its Clinton email probe. In a Feb. 18 interview, agents asked, Paul Combetta, a technician with Clinton’s IT firm, Platte River Networks, about a Dec. 11, 2014, email he sent in which he referred to the “…Hilary [sic] coverup [sic] operation.”

Combetta said the comment was a joke that was a reference to a request from Clinton’s team to change the length of a 60-day email retention policy. (RELATED: FBI Docs: Hillary IT Joked About ‘Cover-up Operation’)

Combetta invoked his Fifth Amendment rights later in the interview. The FBI determined that he provided false statements during the interview.

Mook hemmed and hawed in response to Tapper’s question and eventually blamed Republicans without addressing the email.

“I’m actually glad you asked this question because a lot of this is swirling around in the ether,” began Mook.

“It’s important to pull back and look at the facts here. The FBI did a comprehensive and deep investigation into this,” he continued, noting that FBI director James Comey determined that Clinton should not be charged for any crimes related to her use of the private server.

“So what’s the Hillary cover-up operation that the IT worker was referring to?” Tapper pressed. (RELATED: Hillary’s Campaign Manager Goes Into Full Spin Mode When Asked About ‘Sanctuary Cities’)

Though the “cover-up” email was revealed in FBI documents, Mook blamed Republicans for the release of the damning document.

“Well, this is the perfect example of what’s going on here. The Republicans in the House side are selectively leaking documents for the purpose of making Hillary look bad,” he said.

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