Court papers said Khusyaynova's operation was funded by Russian oligarch Yeveniy Prigozhin and two companies he controls, Concord Management and Consulting LLC and Concord Catering.
As part of her role in the operation, Khusyaynova allegedly oversaw its finances, "including foreign influence activities directed at the United States", the DOJ said. "Our nation is built upon a hard-fought and unwavering commitment to democracy".
The indictment said Yelena Khusyainova was involved in a criminal conspiracy as the chief accountant for Project Lakhta.
Between 2016 and 2018, Project Lakhta's proposed operating budget exceeded $35 million, although only a portion of that money targeted the USA, prosecutors said.
The FBI remains dedicated in its efforts to thwart "unlawful influence operations" with fellow law enforcement agencies, FBI Director Christopher Wray said in the news release, adding that the bureau takes "all threats to our democracy very seriously".
Prigozhin, sometimes dubbed "Putin's chef" because he has managed catering for the Russian leader, was already indicted in February along with 12 other IRA employees over their alleged interference during 2016.
A criminal complaint against Khusyaynova does not include any allegation that the conspiracy had an effect on the outcome of a USA election.
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The Internet Research Agency "tampered with, altered, or caused a misappropriation of information with the goal or effect of interfering with or undermining election processes and institutions", specifically the 2016 U.S. presidential race, the Treasury Department said earlier this year. And, by using the "thousands of social media and email accounts" that were generated, they allegedly tried "to create and amplify divisive social and political content targeting USA audiences", the news release said.
Prosecutors say the conduct singled out on Friday runs afoul of criminal laws that bar foreign nationals from attempting to influence American elections, or from engaging in political activities without first registering with the attorney general.
Since at least 2015, the group created thousands of false social media profiles and email accounts that appeared to be from people inside the US and were aimed to "create and amplify divisive social and political content", including on significant current events, such as deadly shootings in SC and Las Vegas, prosecutors said in court papers. This included the use of virtual private networks and other means to disguise their activities and to obfuscate their Russian origin. "These accounts also were used to advocate for the election or electoral defeat of particular candidates in the 2016 and 2018 USA elections".
While all of the social media identities cited in the indictment have since been removed or blocked, postings by others show their messages were frequently liked, forwarded, and retweeted.
The foreign influence scheme, dubbed "Project Lakhta", was intended "to sow division and discord in the USA political system", the DOJ complaint alleges, by stoking such hot-button issues as immigration, the Confederate flag, gun control and NFL players "taking a knee" during the national anthem.
The accounts were used "to create and amplify divisive social and political content targeting U.S. audiences".