Russia and Iran targeted election infrastructure during the 2020 U.S. vote but did not compromise any of the results, the departments of Homeland Security and Justice said Tuesday.
"Broad Russian and Iranian campaigns targeting multiple critical infrastructure sectors did compromise the security of several networks that managed some election functions," the government agencies said in a joint report.
"But they did not materially affect the integrity of voter data, the ability to vote, the tabulation of votes, or the timely transmission of election results."
Russian, Iranian and Chinese government-affiliated actors also "materially impacted" the security of networks associated with American political organizations, candidates, and campaigns, the report said.
"Several such actors gathered at least some information they could have released in influence operations, but ultimately we did not see any such materials deployed, modified, or destroyed," it said.
The report said there was "no evidence that any foreign government-affiliated actor prevented voting, changed votes, or disrupted the ability to tally votes or to transmit election results."
It specifically rejected a theory floated by lawyers for former president Donald Trump's campaign that a voting tabulation company had links with Venezuela and manipulated election results in favor of his opponent Joe Biden.
The report said the public claims had been investigated and "determined that they are not credible."
The authors of the report said they looked solely at the impact of foreign government activity on the security and integrity of election infrastructure.
"It did not address the effect of foreign government activity on public perception or the behavior of any voters, nor did it address the impact of non-state foreign actors like cybercriminals," they said.
Democratic Sen. Mark Warner, chairman of the Senate Intelligence Committee, said the report "highlights the ongoing and persistent efforts by our adversaries to influence our elections."
"Russia, in particular, has expended real effort, not just in 2020, but also as we all recall in 2016, to influence election results," Warner said.
"The problem of foreign actors trying to influence the American electorate is not going away and, given the current partisan divides in this country, may find fertile ground in which to grow in the future," he said.