NEW YORK (AP) — Foreign adversaries have shown continued determination to influence the U.S. election –- and there are signs their activity will intensify as Election Day nears, Microsoft said in a report Wednesday.

Russian operatives are doubling down on fake videos to smear Vice President Kamala Harris’ campaign, while Chinese-linked social media campaigns are maligning down-ballot candidates who are critical of China, the company’s threat intelligence arm said Wednesday.

Meanwhile, Iranian actors who allegedly sent emails aimed at intimidating U.S. voters in 2020 have been surveying election-related websites and major media outlets, raising concerns they could be preparing for another scheme this year, the tech giant said.

The report serves as a warning – building on others from U.S. intelligence officials – that as the nation enters this critical final stretch and begins counting ballots, the worst influence efforts may be yet to come. U.S. officials say they remain confident that election infrastructure is secure enough to withstand any attacks from American adversaries. Still, in a tight election, foreign efforts to influence voters are raising concern.

Microsoft noted that some of the disinformation campaigns it tracks received little authentic engagement from U.S. audiences, but others have been amplified by unwitting Americans, exposing thousands to foreign propaganda in the final weeks of voting.

Russia, China and Iran have all rejected claims that they are seeking to meddle with the U.S. election.

“The presidential elections are the United States’ domestic affairs. China has no intention and will not interfere in the US election,” the Chinese Embassy said in a statement.

“Having already unequivocally and repeatedly announced, Iran neither has any motive nor intent to interfere in the U.S. election; and, it therefore categorically repudiates such accusations,” read a statement from Iran's mission to the United Nations.

A message left with the Russian Embassy was not immediately returned on Wednesday.

The report reveals an expanding landscape of coordinated campaigns to advance adversaries’ priorities as global wars and economic concerns raise the stakes for the U.S. election around the world. It details a trend also seen in the 2016 and 2020 elections of foreign actors covertly fomenting discord among American voters, furthering a divide in the electorate that has left the nation almost evenly split just 13 days before voting concludes.

“History has shown that the ability of foreign actors to rapidly distribute deceptive content can significantly impact public perception and electoral outcomes,” Clint Watts, general manager of the Microsoft Threat Analysis Center, said in a news release. “With a particular focus on the 48 hours before and after Election Day, voters, government institutions, candidates and parties must remain vigilant to deceptive and suspicious activity online.”

The report adds to previous findings from Microsoft and U.S. intelligence that suggest the Kremlin is committed to lambasting Harris’ character online, a sign of its preference for another Donald Trump presidency.

Russian actors have spent recent months churning out both AI-generated content and more rudimentary spoofs and staged videos spreading disinformation about Harris, Microsoft’s analysts found.

Among the fake videos were a staged clip of a park ranger impersonator claiming Harris killed an endangered rhinoceros in Zambia, as well as a video sharing baseless allegations about her running mate Tim Walz, which U.S. intelligence officials also attributed to Russia this week. Morgan Finkelstein, national security spokeswoman for the Harris campaign, condemned Russia's efforts.

Another Russian influence actor has been producing fake election-related videos spoofing American organizations from Fox News to the FBI and Wired magazine, according to the report.

China over the last several months has focused on down-ballot races, and on general efforts to sow distrust and democratic dissatisfaction. A Chinese influence actor widely known as Spamouflage has been using fake social media users to attack down-ballot Republicans who have publicly denounced China, according to Microsoft’s analysts.

Candidates targeted have included Rep. Barry Moore of Alabama, Sen. Marsha Blackburn of Tennessee, and Rep. Michael McCaul of Texas, all of whom are running for reelection, the report said. The group also has attacked Sen. Marco Rubio of Florida.

All four politicians sent emailed statements condemning China's aggression against American political candidates and its efforts to weaken democracy.

In its statement, the Chinese embassy said U.S. officials, politicians and media “have accused China of using news websites and social media accounts to spread so-called disinformation in the US. Such allegations are full of malicious speculations against China, which China firmly opposes.”

Iran, which has spent the 2024 campaign going after Trump with disinformation as well as hacking into the former president’s campaign, hasn’t been stymied by ongoing tension in the Middle East, according to the Microsoft report.

Quite the opposite, groups linked to Iran have weaponized divided opinions on the Israel-Hamas War to influence American voters, the analysts found. For example, an Iranian operated persona took to Telegram and X to call on Americans to sit out the elections due to the candidates’ support for Israel.

Microsoft's report also said it observed an Iranian group compromising an account of a notable Republican politician who had a different account targeted in June. The company would not name the individual but said it was the same person who it had referenced in August as a “former presidential candidate.”

The report also warned that the same Iranian group that allegedly posed as members of the far-right Proud Boys in intimidating emails to voters in 2020 has been scouting swing-state election-related websites and media outlets in recent months. The behavior could “suggest preparations for more direct influence operations as Election Day nears,” Watts said.

Iran's mission to the United Nations said in a statement that the allegations in the report “are fundamentally unfounded, and wholly inadmissible.”

Even as Russia, China and Iran try to influence voters, intelligence officials said Tuesday there is still no indication they are plotting significant attacks on election infrastructure as a way to disrupt the outcome.

If they tried, improvements to election security means there is no way they could alter the results, Jen Easterly, director of the U.S. Cybersecurity and Infrastructure Security Agency, told The Associated Press earlier this month.

Intelligence officials on Tuesday also warned that Russia and Iran may try to encourage violent protests in the U.S. after next month’s election, setting the stage for potential complications in the post-election period.

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