Election interference is happening "right now," according to Obama-era Homeland Security Secretary Jeh Johnson, who warned Americans to be wary of foreign propaganda campaigns and urged them to cast ballots.
"It's up to the voters to be informed and look past the disinformation that is out there," Johnson said during an interview with "Face the Nation" on CBS on Sunday.
"The Iranians have attempted to intimidate Democratic voters," he said. "We know that there was a large-scale targeting exercise by the Russian government, but our government does not know exactly what their plan is. So there is, in fact, foreign interference. And so I'm encouraged that DHS is taking this very seriously. They plan for this. They've had four years to plan for this, but there's no complete line of defense against a sophisticated foreign actor."
Last month, intelligence officials revealed a foreign scheme by Iran to target Democratic voters in key swing states by sending them emails that appeared to be from the Proud Boys, an alt-right group in the U.S.
Officials also said that there was evidence that Russia had access to voter databases throughout the country but the Kremlin appears not to have utilized it.
Johnson said he cannot deny "the possibility of tension, some unrest on Election Day and in the immediate aftermath, but said, "none of this discussion should discourage people from participating in voting and exercising their right and their responsibility to vote."
Several states across the country, including New York, Pennsylvania, Washington, D.C., and Arizona, are bracing for unrest in the aftermath of election night, strengthening police presence and boarding up businesses to guard against potential looting.
"It's really on Americans to have faith in our democratic process," he said. "Roughly one half of the country — and this is a very emotional election — roughly one half of the country after next Tuesday is going to be bitterly disappointed."
"I'm encouraged that more than 90 million Americans have already cast their ballots, which, if you do the math, is the equivalent of the entire 1996 presidential election. And so I remain optimistic, but we cannot discount the possibility of some trouble or unanticipated events, given the tension that exists out there."