WASHINGTON D.C. (CBSNewYork) — While President Donald Trump’s Twitter feed remained quiet during former FBI Director James Comey’s testimony in front of the Senate Intelligence Committee on Thursday, his son Donald Trump Jr. declined to hold back.

The president’s son zeroed in on statements made by Comey during his testimony Thursday, using various emojis to accompany text and at one point asking “Is this a joke?”

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He also made reference to ‘the swamp’ a term used frequently during the 2016 campaign to refer to day-to-day proceedings and political figures in the beltway and said, “Washington DC at its finest. This is what America rallied against, but the DC elite don’t get it or know any other way.”

In a later tweet he appeared to mock Comey over a response he gave when questioned about a discussion with President Trump.

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He then went on to refer to ask if Comey’s testimony was ‘a joke.’

In his first public remarks since being fired by President Donald Trump on May 9, Comey told the Senate Intelligence Committee Thursday that he documented his conversations with the president because he “was honestly concerned that he might lie about the nature of our meeting.”

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Those expecting President Trump to respond with a flurry of tweets may have been disappointed to hear CBS News’ Meg Brennan report, that the president was watching Thursday’s hearing with his lawyer.