'Tit for tat with Russia not good': Private undisclosed emails leaked from the Mueller investigation
Robert Mueller was named as an independent prosecutor to lead the Russia investigation in May 2017. (AFP / MANDEL NGAN)

Private, previously undisclosed emails in connection with special counsel Robert Mueller's investigation into former President Donald Trump have now come to light.

On Monday, May 3, Buzzfeed News and CNN received a cache that included more than 300 pages of documentation from the investigation. The publication reports that the robust compilation of documents — which consist of "emails, text messages, and memos seized from subjects and witnesses" — contain details about correspondence between members of Trump's campaign as they discussed Russia.

A review of the records indicates that Trump's son, Donald Trump, Jr., his daughter Ivanka Trump, and his son-in-law Jared Kushner, were heavily involved in the discussions at the onset of the former president's campaign. In fact, Ivanka reportedly informed the co-chair of her father's campaign that her brother, Donald Jr. could make recommendations for military advisors while Kushner offered details about his private meeting with Henry Kissinger.

In a document titled, "National Security Memo 4," Sebastian Gorka, who later became an adviser to the president issued a warning to the Trump campaign insisting that "Russia was a 'criminal enterprise' and that Putin would only respond to 'a determined show of force.'"

Some of the documents had previously been redacted due to the Justice Department and FBI's concerns about privacy, national security, and other law enforcement investigations.

Records also include documentation from September 2015 when former national security adviser, Michael Flynn, solicited Trump's former campaign strategist Steve Bannon. In December 2016, text message records also revealed details about Flynn's conversations with Sergey Kislyak, the former Russian ambassador to the United States. At the time, Flynn was said to be working to "contain the fallout."

The records also include the text messages surrounding Flynn's December 2016 communications with Russia's former ambassador to the US, Sergey Kislyak, and Flynn's efforts to contain the fallout. A month into his job as national security adviser, Trump fired Flynn for lying to Vice President Mike Pence about those communications. Flynn later pleaded guilty to lying to FBI agents about it.

When the Obama administration announced its intent to enforce sanctions on Russia for allegedly interfering in the 2016 presidential election, Flynn received a text message from a mystery sender that included a link to the New York Times article titled, "U.S. Punishes Russia For Election Hacking, Ejecting Operatives."

In response, Flynn wrote, "Time for a call???"

The unknown recipient wrote, "Yes. KT on with bossert," an apparent reference to Tom Bossert, Trump's homeland security adviser.

Flynn wrote back: "Ok. Tit for tat w Russia not good. Russian AMBO reaching out to me today."

The documents also included emails sent by Trump's infamous political operative Roger Stone, who he also pardoned. Those emails were sent between 2015 and 2016 as he advised the soon-to-be president on a number of policies. The Trump campaign has yet to respond to the latest reports.