Fox News this week attacked Army Lt. Col Alexander Vindman, a Purple Heart recipient who testified Tuesday in the impeachment inquiry into President Donald Trump.

Vindman, who serves as the top Ukraine expert on the National Security Council, told impeachment investigators he listened in on Trump’s July 25 phone call with Ukrainian President Volodymyr Zelensky. The decorated veteran said in his testimony he believed Trump undermined national security by pressuring Zelensky to investigate Joe Biden and his son.

Ahead of Vindman’s testimony, Fox News host Laura Ingraham questioned his loyalty to Trump and even appeared to suggest he was unpatriotic for choosing to testify against the president. Ingraham pointed to the fact that The New York Times’ story this week about Vindman’s concerns over Trump’s interactions with Zelensky reported that the veteran came to the United States from Ukraine as a child and that officials in the country asked him in English about recommendations for negotiating with Trump’s personal lawyer Rudy Giuliani. The Ingraham Angle host then said she believed Vindman was “working against the president’s interests” from inside the Trump administration.

“Isn’t that kind of an interesting angle on the story?” Ingraham asked her guest John Yoo, a former Justice Department attorney who assisted with writing the famous “torture memos” during the Iraq War while President George W. Bush was in office.

“I find that astounding,” Yoo replied. “Some people might call that espionage.”

Several people, including MSNBC host Brian Williams, quickly condemned Fox News’ accusations against Vindman, who was injured from a roadside bomb in Iraq in 2004.

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Williams called the network’s attacks against Vindman “an opening salvo in character assassination,” and the MSNBC host’s guest Jeremy Bash agreed.

“I think they’re alleging a U.S. Army colonel is a traitor,” said Bash, a former CIA chief of staff. “Here we have the followers of Donald Trump doing what I think is absolutely despicable, which is claiming that not only is he against Trump but he’s un-American and I don’t think Republicans, Democrats, anybody who cares about our country, are going to stand for that.”

Nicole Wallace, a political analyst for MSNBC, also slammed Ingraham, Yoo and Rep. Sean Duffy (R-Wisconsin) for their attacks against Vindman by calling them “chickens—t.”

“He passed a background check that the President’s daughter and son-in-law didn’t,” Wallace said, referring to Vindman.