Foreign adversaries, especially Russia, will intensify their influence efforts in the final two weeks before the U.S. election and will seek to create uncertainty and undermine the legitimacy of the election process well after the polls have closed, federal intelligence officials warned on Tuesday.

In addition, the country’s clandestine community is “increasingly confident” Russian-linked actors are considering a range of inclunce efforts, including inciting violence and questioning the validity of democracy as a political system, regardless of who wins the presidential race next month.

Other foreign actors, principally Iran and China, “remain intent on fanning divisive narratives to divide Americans and undermine Americans' confidence in the U.S. democratic system,” an official from the Office of the Director of National Intelligence told reporters during a conference call.

In the latest example they have shared with the public, the intelligence agencies have assessed that Russia was responsible for a video that circulated widely last week on social media purporting to show a former student of Democratic vice presidential nominee Tim Walz.

Russian “influence actors created and amplified content alleging inappropriate activity committed by the Democratic vice presidential candidate during his earlier career,” the ODNI official said, later adding “one of their tactics they use is these stage direct to camera videos and trying to make them go viral.”

The U.S. previously blamed Moscow for fake videos meant to denigrate Vice President Kamala Harris, the Democratic presidential nominee.

The federal government has taken action against a number of Russian influence operations in recent months, including uncovering a network of websites that spoofed real U.S. news outlets to share phony articles generated with artificial intelligence and indicting two employees of Russian state broadcaster RT for a scheme that paid millions to right-wing influences who posted clips opposing aid to Ukraine.

The officials and others stressed Tuesday that they did not think it was likely for a foreign government to interfere with voting itself or manipulate votes after they had been cast. Rather, actors could pounce on routine disruptions that occur every Election Day to undercut the entire process.

The spy community also shared an unclassified version of a document from earlier this month that raised concerns about foreign influence threats through the post-election processes, including tabulation, unofficial reporting, the certification in January and even the next inauguration. 

The ODNI official cautioned that the intelligence community does not view that period as “more significant” than the upcoming two weeks.

“What we would say is, they have more experience based on 2020 and they likely learned lessons from what occurred last time,” the official said. “It's also fair to say that many of these countries did not have full appreciation for the various election processes that happen after polls close, and they have greater awareness of the significance, they have greater ability to attempt to disrupt them.”

Iran, likewise, could encourage protests and violence during that period, and  Russia would likely become more aggressive should Republican former President Donald J. Trump lose to Harris, the official said. They would not say if specific states are being targeted for such incidents, or if particular groups of voters are at risk.

Another ODNI official said the experts group within the government’s election security community has ramped up its efforts as Election Day draws closer, meeting six times last week alone. 

An official from the Cybersecurity and Infrastructure Security Agency (CISA) said voters should “expect disruptions.”

“We're going to see a voting location lose power. We're going to see potentially some type of impact on a transportation system. We're going to see a potential ransomware attack against a local election office. We may see an election night reporting website experience” a distributed denial-of-service (DDoS) attack, they said. DDoS incidents flood sites with junk traffic with the intention of knocking them offline.

“We're going to see those things go wrong, and what is so important to remember is that it's OK. While it may be disruptive, it will not impact the security or integrity of the vote counting or casting process.”