New York CNN  — 

Special Counsel Robert Mueller chose to lay out in detail in his Russia investigation report the role that prominent Trump campaign officials, Trump critics and the media unwittingly played in promoting messages sent by a Russian troll group with links to the Kremlin. The details could serve as a warning to Americans to think before they tweet.

The report, released Thursday, outlines among other things how the troll group, which Mueller indicted last year, engaged in a years-long campaign to sow discord in the U.S., and eventually to support the election of Donald Trump, by creating and maintaining fake social media personas and activist organizations designed to look like they were run by real Americans.

The troll group, known as the Internet Research Agency (IRA), also successfully used fake accounts on Twitter to provoke reactions from high profile American users from across the political spectrum.

The report makes clear that Mueller’s team found no evidence that Americans who had interacted with the accounts knew they were tied to Russia or any other foreign country.

But whether those Americans knew — and even whether they were retweeting the fake accounts to support what they had said or publicly disagreeing with them — may not have mattered to the trolls. Any interaction between one of the accounts and someone with a significant number of Twitter followers would have gotten the account in front of more people, and likely led to new followers. The more followers the accounts got, the more legitimate they would have looked to both regular users and high-profile ones alike.

The report names former Ambassador Michael McFaul, political operative Roger Stone, Fox News host Sean Hannity, and Michael Flynn Jr., the son of Trump’s former national security adviser, as either responding to or retweeting tweets sent by the Russian group.

Responding to the report on Thursday, McFaul, who served as US ambassador to Russia under President Obama, tweeted, “for heaven’s sake. I was not ‘influenced’ by these Russian bots (and I engaged with hundreds more , bots and real people). I was trying to refute them.”

Tweets from one troll account, @TEN_GOP, which was designed to look like it was associated with the Republican party of Tennessee, were cited or retweeted by multiple Trump campaign officials or surrogates. Among those who interacted with the account were Trump’s sons Donald Trump Jr. and Eric Trump, along with Kellyanne Conway, who is now counselor to the president, and Brad Parscale, who is now the campaign manager for Trump’s reelection campaign.

“The investigation identified no similar connections between the IRA and the Clinton Campaign,” the report noted.

Trump’s own social media account interacted with an IRA account in September 2017, according to the report. Responding to a tweet from the Russian-controlled account @10_gop that read, “We love you, Mr. President,” the president’s account tweeted back, “So nice, thank you.”

In August 2016, Trump’s Facebook page posted pictures from an event that was part of a series of events supporting his candidacy in Florida, along with a message of thanks. While real Americans attended the series of events in Florida, Mueller alleges that the Russian group were involved in the organization of it.

Employees of the Russian troll group were monitoring the reaction of the Trump campaign, and later the Trump administration, to its posts, according to the Mueller report. After Trump’s Facebook page posted about the Florida event, an IRA employee, using a false persona, sent a message to a real American Tea Party activist, saying, “Mr. Trump posted about our event in Miami! This is Great!,” according to the report.

The report also cites articles by the Washington Post and U.S. News and World Report that included posts from the Russian group. CNN has previously reported that multiple American news outlets, including CNN itself, had unwittingly used tweets posted by the Russian group. The tweets normally appeared in stories where news outlets used tweets from random Twitter users when attempting to summarize public sentiment on a given issue.

CNN found that U.S. news outlets had continued to use tweets from the Russian group as recently as 2018.