The military could not have done more the stop the Benghazi terrorist attacks as they unfolded, the former chief counsel for the House Benghazi investigation said on multiple occasions, according to panel Democrats.

Former Republican Chief Counsel Dana Chipman said in closed-door interviews with Pentagon officials that the military acted properly during the attacks in 2012, Reps. Elijah Cummings (D-Md.) and Adam Smith (D-Wash.) revealed Sunday in a letter to committee chairman Trey Gowdy (R-S.C.).

Chipman left the House Select Committee on Benghazi in January and took a position with the Federal Judicial Center, an education and research agency. His departure came as the now two-year-old Benghazi panel faced mounting accusations of political animus against Democratic presidential candidate and former Secretary of State Hillary Clinton.

“Sir, I don’t disagree with the actions you took, the recommendations you made, and the decisions you directed … I don’t mean to suggest that anything could have been done differently to affect the outcome in Benghazi,” Chipman told former Defense Secretary Leon Panetta on Jan. 8, according to the letter.

“We could not have affected the response to what occurred by 5:15 in the morning on the 12th of September in Benghazi Libya … You can debate what’s timely, what’s untimely, but nothing could have affected what occurred in Benghazi,” Chipman said to former Pentagon chief of staff Jeremy Bash on Jan. 13, the letter stated.

Republicans have questioned the military’s response to the Benghazi attacks, suggesting four Americans might not have been killed that night had leaders such as Panetta and Clinton acted differently. Chipman’s comments challenge this view, and Democrats are using them as ammunition to cast further doubt on the embattled panel’s credibility.

“The conclusions of your former Republican Chief Counsel match almost exactly the findings — from more than two years ago — of the House Committee on Armed Services, which conducted its own investigation into the attacks in Benghazi,” Cummings and Smith wrote.

“Rep. Buck McKeon, the Republican Chairman of the Committee who led that investigation, concluded at the time, ‘I think I’ve pretty well been satisfied that given where the troops were, how quickly the thing all happened and how quickly it dissipated, we probably couldn’t have done more than we did.'”

Democrats also accused Republicans of making an unreasonable slew of interview requests with the Defense Department to “pad their numbers” after a widely criticized public hearing with Clinton in October.

Cummings is the Select Committee’s ranking Democrat. Smith, who also serves on the panel, is the top Democrat on the Armed Services Committee.

Gowdy spokesman Matt Wolking fired back in a statement.

“No matter how many dishonest letters Democrats waste time writing, Republicans will continue conducting a thorough, fact-centered investigation that includes all relevant witnesses, regardless of rank,” Wolking stated.

“Democrats have peddled the same politically motivated, predetermined conclusions from the very beginning, so it’s no surprise they’re still clinging to their false claim everything has been ‘asked and answered’ … Democrats’ false attacks on legitimate congressional oversight are proof they’re nervous about the new information committee investigators have uncovered.”

Wolking distributed a statement from Chipman defending the panel’s interview requests. It did not address Chipman’s comments to Panetta and Bash.

“I agree with Chairman Gowdy. If some witnesses refer the committee to other witnesses, the responsible thing to do is interview them. The committee has an obligation to the American people to determine what can and cannot be substantiated, so if an individual makes public allegations about Benghazi, the committee should interview that person,” Chipman stated.

A request for additional comment from Chipman by email was not returned.

Tensions are once again on the rise within the Benghazi panel as the 2016 election season gets underway.

Democrats argue Gowdy is drawing out release of his final investigative report to damage Clinton once she becomes the Democratic nominee. Republicans defend their probe as impartial and say the lengthy time frame is necessary to ensure its completeness. The GOP plans to release the final report before summer, they have said.