Washington (CNN) Kristin Davis, a former employee and close friend of Roger Stone, said after testifying before a grand jury, she sensed special counsel Robert Mueller's team was concerned with what Stone might have had prior knowledge of before the 2016 election.

"I think there's the general concern for some things that he seemed to predict," Davis said on CNN's "Cuomo Prime Time" Monday night.

Davis pointed to "the Podesta tweet" in particular -- an apparent reference to a tweet Stone sent in the heat of the 2016 campaign, where he said, "It will soon the Podesta's time in the barrel." That tweet in August came weeks ahead of WikiLeaks' publication of Hillary Clinton campaign chairman John Podesta's emails, which were hacked by Russia, according to the US intelligence community.

previous CNN review showed that outside of that tweet, Stone repeatedly claimed he knew about future WikiLeaks dumps.

Stone is a longtime acquaintance and supporter of President Donald Trump, and his name has continued to come up as the investigation into potential coordination between Russia and members of Trump's orbit has continued. Davis is more widely known as the "Manhattan Madam" and was set last week to testify before a grand jury convened for the special counsel investigation led by Mueller, a former FBI director.

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