Rep. Devin Nunes (R-California) mistakenly addressed the National Security Council’s Ukraine specialist Lt. Col. Alexander Vindman as “Mr. Vindman” during the House of Representatives impeachment hearings on Tuesday. Vindman corrected at once the title given to him by Nunes.

Vindman responded to Nunes, when questioned by the lawmaker, “Ranking member, it’s Lt. Col. Vindman, please.” Nunes was soon disparaged on Twitter as the moment became viral. The #DevinNunesisanidiot soon became trending topic on Twitter. There were more than 20,000 tweets skewering Nunes.

Nunes, the ranking member of the House Intelligence Committee, grilled Vindman during his testimony in the publicly televised House Impeachment Investigation of President Donald Trump.. Nunes reminded Vindman of his closed-door deposition in the House previously where the officer had had said he did not know the whistleblower.

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Vindman replied that he discussed the Ukraine issue with the Deputy Assistant Secretary of State George Kent and an unidentified member of the intelligence community. Both Kent and the other unknown person were privy to updates in Ukraine news. This anonymous person is said to be the whistleblower.

Nunes pressed Vindman into revealing the identity of the whistleblower. Vindman did not expose the whistleblower despite being goaded by Nunes.

Nunes tried to convince Vindman in disclosing the name of the person who catalyzed the presidential impeachment investigation. Nunes said, “You can plead the Fifth but you’re here to answer questions and you’re here under subpoena. So you can either answer the question or you can plead the Fifth.” The House Intelligence Committee Chairman Adam Schiff then intervened. Schiff said the whistleblower has a “statutory right to anonymity” and stopped the line of questioning.