"And frankly, it's heartbreaking for me as a guy who served our country in uniform and out of uniform. It is so heartbreaking because I was the guy that went around the world as a military officer and certainly as a leader, promoting American values and promoting what America is all about.

And here we have a president, President Obama, who, it is very clear, committed some type of egregious act," Flynn said during an appearance on "Ron Schmitt Tonight."

Flynn said that while he wouldn't label the actions of the Obama administration treason, he said it was "the greatest crime in the history of the United States" and the whole experience has been surreal. "I see what is coming out. I watched Tulsi Gabbard at her press conference today. This is really, really serious stuff," he added.