Newly released audio recordings from Joe Biden's conversations with ghostwriter Mark Zwonitzer during work on his 2017 memoir capture him discussing classified materials and at times appearing to lose his train of thought. The recordings surfaced Monday following a lengthy legal battle and were previously reviewed during Special Counsel Robert Hur's investigation into Biden's handling of classified documents.

The heavily redacted recordings, totaling roughly 70 hours, were released to the House Judiciary Committee and the conservative Oversight Project after two years of litigation. The conversations took place while Biden worked with Zwonitzer on the memoir Promise Me, Dad: A Year of Hope, Hardship, and Purpose.

In one segment, Biden discusses discovering classified materials among his personal papers, saying, "So this was, I early on, um, in '09 I just found all the classified stuff downstairs." At another point, he cautions Zwonitzer about documents under review, stating, "Some of this may be classified so be careful with it. I'm not sure... It's not marked classified but -"

According to Hur's final report, Biden read "nearly verbatim" From notebooks containing sensitive national security and foreign policy information while working with the ghostwriter. The recordings also capture Biden apparently realizing in real time that certain documents contained classified information, saying in one exchange, "The next thing I have here is, um, this is classified..."

According to CBS News, which first reviewed the tapes, Biden also discussed White House meetings that may have involved classified information. One recording dated October 10, 2016, includes Biden speaking about notes he had retained without others realizing it: "I have extensive notes over this period of time... They didn't know I have this."

The audio also includes several moments in which Biden appears to struggle to recall information or lose his train of thought, including instances where he says, "Alright, what was I going to ask you? Something else... Uh... um. Oh gosh. I can't think of anything else."

Hur concluded that Biden "willfully retained and disclosed classified materials" After leaving office as vice president but declined to pursue criminal charges.