The House Select Committee on Benghazi will interview top Hillary Clinton aide Huma Abedin behind closed doors on Friday, sources familiar with the committee told NBC News Wednesday evening.
The interview comes just days before Hillary Clinton is scheduled to testify before the committee herself during a public hearing on October 22.
The interview of Abedin is one of many sessions the committee has had with people who were close to Clinton during the September 11, 2012 attack on the American diplomatic compound in Benghazi.
Ex-Chief-of-Staff Cheryl Mills participated in an interview before the committee on September 3, and former Deputy Chief-of-Staff Jake Sullivan was interviewed on September 4.
On June 17 the committee deposed Clinton confidant Sid Blumenthal, and on September 10 her former IT staffer Bryan Pagliano plead the fifth before a closed meeting.
The Benghazi investigation has recently been rocked by allegations that the probe has been purely political. Last week, a former investigator for the committee on Benghazi claimed he was unfairly fired for trying to conduct a non-partisan and "thorough" probe instead of focusing primarily on Clinton.
And in comments made late last month, House Majority Leader Kevin McCarthy linked the committee's existence to Clinton's falling poll numbers. McCarthy later said he misspoke, and never intended to imply the committee was politically motivated.
Earlier on Wednesday, Rep. Richard Hanna, R-NY, said McCarthy was right.
“Sometimes the biggest sin you can commit in D.C. is to tell the truth,” Hanna said in an interview with Keeler in the Morning, a show on WIBX radio in upstate New York. “This may not be politically correct, but I think that there was a big part of this investigation that was designed to go after people and an individual, Hillary Clinton,” Hanna said.
Clinton's campaign pounced on the admission.
"House Republicans aren't even shy anymore about admitting that the Benghazi Committee is a partisan farce," said Clinton spokesman Brian Fallon. "After failing to produce any new information on the tragic 2012 attacks at Benghazi despite a 17-month investigation, John Boehner has reportedly urged the committee to shift its focus to Hillary Clinton's emails in an ongoing effort to try to hurt her politically. Hillary Clinton will still attend next week's hearing, but at this point, (Chairman) Trey Gowdy's inquiry has zero credibility left."