Updated

The chairman of the House Benghazi panel is firing back at the Defense Department for criticizing the Republican-led investigation into the deadly 2012 attacks in Benghazi, Libya.

Congressman Trey Gowdy of South Carolina says a senior department official intentionally mischaracterized the panel's inquiry. Gowdy also calls the official's assessment "overtly partisan."

Gowdy's response is outlined in a letter sent Friday to Defense Secretary Ash Carter.

In an April 28 letter to Gowdy, assistant secretary of defense Stephen C. Hedger expressed frustration with what he called the Benghazi panel's potentially futile calls for witnesses and information. Hedger also challenged a line of questioning of current and former military officials that focused on hypotheticals suggested by committee members or staff.

Gowdy says Hedger's letter is filled with factual inaccuracies.