Washington (CNN) Embattled FBI agent Peter Strzok on Thursday defended a controversial text he sent disparaging Donald Trump during the 2016 presidential campaign by saying it was written in response to "then-candidate Trump insulting the immigrant family of a fallen war hero."

The text exchange at issue was detailed in a recently-released Justice Department internal watchdog report , which revealed that on August 8, 2016, now ex-FBI lawyer Lisa Page wrote in a text, Trump is "not ever going to become president, right? Right?!" to which Strzok replied, "No. No he's not. We'll stop it."

During a contentious congressional hearing on Thursday, Strzok attempted to explain why he sent the message in the first place.

"In terms of the texts that 'we will stop it,' you need to understand that was written late at night, off-the-cuff, and it was in response to a series of events that included then-candidate Trump insulting the immigrant family of a fallen war hero, and my presumption, based on that horrible, disgusting behavior that the American population would not elect somebody demonstrating that behavior to be President of the United States," Strzok said.

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