The report from former special counsel Robert Mueller, detailing Russia’s interference in the 2016 presidential election and the Trump administration’s efforts to obstruct the inquiry, was the most hotly anticipated prosecutorial document in a generation. But at 448 pages, it reflected only a tiny fraction of the primary-source documents that the government amassed over the course of its two-year investigation.

[Here’s the second installment of documents.]

Using the Freedom of Information Act, BuzzFeed News sued to gain access to those documents, which are key to understanding this important chapter in American history.

Today, in response to a court order, the Justice Department has released the second installment: summaries of FBI interviews spanning hundreds of pages. These summaries, known as “302 reports,” are some of the most important and highly sought-after documents from Mueller’s investigation. They contain numerous redactions, which BuzzFeed News will challenge in our ongoing lawsuit.

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The cache released last month included 302s from key players like Trump’s former personal lawyer Michael Cohen, deputy Trump campaign manager Rick Gates, and former White House official Steve Bannon. They contained explosive details that were not cited in Mueller’s report. For example, in an April 2018 interview with the special counsel’s office, Gates told investigators that while Paul Manafort was running Trump’s campaign, he had pushed the unfounded theory that it was Ukraine, not Russia, that had hacked the Democratic National Committee’s servers. That theory has been thoroughly debunked by the US intelligence community, but Trump still cites it — most notably during the July 2019 call with Ukrainian President Volodymyr Zelensky, which is at the heart of the current impeachment investigation.

[We want your help! If you see something in these memos, you can email reporter Jason Leopold at jason.leopold@buzzfeed.com or reach us securely at tips.buzzfeed.com.]

The 302s are just the beginning. BuzzFeed News is pursuing five separate lawsuits to pry loose all the subpoenas and search warrants that Mueller’s team executed, as well as all emails, memos, letters, talking points, legal opinions, and financial records it generated. In short, we asked for all communications of any kind that passed through the special counsel’s office. We also requested all the documents that would reveal the discussions among Attorney General Bill Barr, former deputy attorney general Rod Rosenstein, and other high-ranking officials about whether to charge Trump with obstruction.

In response, Justice Department lawyers claimed the volume of records requested could total 18 billion pages and take centuries to produce.

For Monday’s installment, the government processed 506 pages, produced 231 pages, and redacted the records citing ongoing investigations, grand jury proceedings, and numerous other FOIA exemptions.

Our full coverage of the Mueller Report’s secret memos