The FBI said on November 5 that polling locations in several U.S. states have been the target of bomb threats, many of which appear to originate from Russian domains.
At least two U.S. polling stations in the state of Georgia were evacuated because of the threats, officials said.
Both reopened after about 30 minutes and authorities are seeking a court order to extend voting hours beyond the statewide closing time of 7 p.m. to make up for the time lost during the evacuations.
Georgia Secretary of State Brad Raffensperger said Russian interference was behind the bomb threats and that, after an investigation, they weren't deemed credible by the FBI.
"They're up to mischief, it seems. They don't want us to have a smooth, fair, and accurate election, and if they can get us to fight among ourselves, they can count that as a victory," Raffensperger told reporters.
“I want to make sure that everyone in Georgia understands this: Russia picked on the wrong Georgia. They need to pick on the other one, in the Black Sea,” Raffensperger added.
WATCH: Voters in Chicago's Ukrainian community talked about their hopes and fears as they headed to the polls in the November 5 U.S. presidential election.
Georgia alone received more than two dozen phony bomb threats on Election Day, an FBI official told Reuters.
U.S. intelligence and security officials earlier accused Russia and Iran of ramping up cyberattacks and disinformation campaigns to sow discord in the tense presidential election.
Russian-linked influence actors "are manufacturing videos and creating fake articles to undermine the legitimacy of the election, instill fear in voters regarding the election process, and suggest Americans are using violence against each other due to political preferences," said a statement issued by the Office of the Director of National Intelligence, the FBI, and the U.S. Cybersecurity and Infrastructure Security Agency on November 4.
"These efforts risk inciting violence, including against election officials," it added.
The FBI said in a separate news release on November 5 that it was made aware of two instances of its name and logo being misused in promoting false narratives surrounding the election.
The first is a fabricated news clip purporting to be a terrorist warning issued by the FBI. The news clip reports falsely that the FBI purportedly stated that Americans should “vote remotely” due to a high terror threat at polling stations, the statement said.
"This video is not authentic and does not accurately represent the current threat posture or polling location safety," it said.
The second instance is a video containing a fabricated FBI press release alleging that the management of five prisons in Pennsylvania, Georgia, and Arizona rigged inmate voting and colluded with a political party.
"This video is also not authentic, and its contents are false," the FBI said.
The statement didn't say where the fabricated material came from.
U.S. intelligence agencies have warned for months of Russian government-backed efforts to influence the vote that pits former President Donald Trump, the Republican candidate, and his opponent, Democratic Party nominee Vice President Kamala Harris.
Opinion polls ahead of Election Day say the race is too close to call, raising tensions as voters head to the polls after an acrimonious campaign.
Polls opened at 5 a.m. on November 5 in some eastern states and will continue across the country, including in Alaska and Hawaii, until the evening hours in those far western U.S. states in a battle between Trump and Harris.
Highlighting an example of the disinformation tactics being used, the U.S. agencies said in the November 4 statement that Russian influence actors recently posted and amplified an article falsely claiming that U.S. officials across swing states plan to orchestrate election fraud using a range of tactics, such as ballot stuffing and cyberattacks.
They also said Russian influence actors manufactured and amplified a recent video that falsely depicted an interview with an individual claiming election fraud in Arizona, which involved creating fake overseas ballots and changing voter rolls to favor Harris.
The Arizona secretary of state has already refuted the video's claim as false.
While "Russia is the most active threat," the statement said Iran also remains a "significant foreign influence threat" to the election.
"We have assessed that Iran has conducted malicious cyberactivities to compromise former President Trump's campaign," the intelligence agencies said.
"Iranian influence actors may also seek to create fake media content intended to suppress voting or stoke violence, as they have done in past election cycles."
The agencies urged voters to "seek out information from trusted, official sources, in particular state and local election officials" in light of the "continued influence efforts by foreign adversaries and the increasing volume of inauthentic content online."
Both Tehran and Moscow have denied playing a role in any disinformation campaigns during the U.S. presidential election.
The outcome of the election may affect Ukraine more than any other foreign country.
The candidates have staked out two very different positions on support for Ukraine, whose defense against invading Russian troops is heavily dependent on U.S. military, financial, and diplomatic support.
Harris has said she would continue President Joe Biden's policy of aiding Ukraine, clearly expressing the desire to see Russia defeated.
Trump has questioned U.S. support for Ukraine, saying Europe should be carrying the bulk of the burden in backing Kyiv against the Russian invasion, and has left NATO's future in doubt.