Lt. Col. Alexander Vindman, the first person to testify as part of the ongoing impeachment inquiry who personally listened in on Trump’s July 25 call with the Ukrainian president, told House lawmakers that the White House reconstruction of the discussion had key omissions, The New York Times reported.

Vindman, a decorated Army officer and the top Ukraine expert on the National Security Council, appeared in front of lawmakers for more than 10 hours on Tuesday, the latest official to defy White House orders to share their direct knowledge of the call that set off the impeachment inquiry. According to his prepared remarks, which were obtained by HuffPost, he said he twice reported his concerns about the call and about President Donald Trump’s demands for a quid pro quo involving military aid and political dirt to one of his superiors, worrying that the exchange could affect national security. Trump reportedly sought a probe of political rival Joe Biden and his son, along with investigations based on conspiracy theories about 2016 campaign manipulation.

But Vindman, who testified before members of three House committees leading the impeachment inquiry, also shed new light on the White House reconstruction of the call, which was released last month. Vindman reportedly told the lawmakers that the document omitted crucial words and phrases that he attempted to see put back in the readout: Some of the changes were ultimately made, but others were not. He did not speculate on the reasoning behind the omissions.

The Wall Street Journal later confirmed the Times’ reporting. Vindman’s lawyer did not immediately return a request for comment.

The Times noted that the missing words do not change the basic contents of the document and there are several other examples of Trump pressuring Ukrainian President Volodymyr Zelensky for politically motivated investigations. But the Times reported that they provide more context about a number of questionable ellipses in the readout and raise further questions about how the White House handled the transcript of the call, which was stored on a secure server usually reserved for highly classified material.

Vindman, a decorated Iraq War veteran who was awarded the Purple Heart, also told lawmakers on Tuesday he didn’t think it was “proper to demand that a foreign government investigate a U.S. citizen,” saying he was troubled that any investigation would “likely be interpreted as a partisan play.” He said he reported his concerns several times to a superior on the National Security Council and defended his actions, saying “any good military officer should and would do the same.”

His lengthy testimony on Tuesday drew praise from Democratic leaders. House Intelligence Committee Chairman Adam Schiff (D-Calif.) said he hoped Vindman’s “example of patriotism will be emulated by others.”

“I want to say also how deeply appalled I was at the pernicious attacks on him last night on Fox,” Schiff said, according to The Washington Post. “The suggestion that because he’s of Ukrainian origin he has some kind of dual loyalty — this Purple Heart recipient deserved better than that scandalous attack.”

But Trump allies spent most of the day attempting to smear Vindman and his potentially damning testimony, which echoed that of other senior administration officials who voiced their concerns about the president’s demands that Ukraine investigate Biden and his son Hunter, who had served on the board of a Ukrainian energy company.

The Army officer’s history in the military, however, was hard for some Republicans to ignore. Senate Majority Leader Mitch McConnell (R-Ky.) refused to “question the patriotism of any of the people coming forward,” Sen. Mitt Romney (R-Utah) called Vindman a “decorated American soldier,” and Sen. Joni Ernst (R-Iowa) said that attacks were “inappropriate” and called the man “honorable.”

Democratic leaders said this week that they will vote to formalize the impeachment inquiry on Thursday amid blistering criticism from Republicans who have accused the party of holding the hearings in secret. GOP lawmakers have been involved in every hearing thus far.