A top US official for election security said his biggest worry is the possibility of outside interference in a likely slow count of the votes the day after the November 3 presidential contest.
Bill Evanina, director of the National Counterintelligence and Security Center, said that external actors could use hacks like ransomware and other cyberattacks against the infrastructure for delivering, counting and transmitting the votes, which includes the overburdened and understaffed post office and polling stations.
"I'm worried about election day on," Evanina told the US Chamber of Commerce in a video briefing Wednesday.
"I'm worried about ransomware attacks. I'm worried about cyberattacks. I'm worried about the inability of people to vote because of cyber penetrations and ransomware."
Ransomeware is a technique used by hackers to completely freeze and block access to all data on a system to extort payments.
Evanina warned that an expected surge in by-mail voting could very well leave the result of the contest between President Donald Trump and challenger Joe Biden, as well as numerous congressional contests, unresolved the day after the election.
"We are in for a rocky 70-plus days coming up," he said.
"We need to prepare as a nation that the election will not be decided on November 3."
"We need to be patient, and understand that, with the mail-in votes that are coming, and the electoral process, we might not have a decided president on the morning of the 4th," he said.
"It's going to take some time to count the votes."
Evanina said he remains on guard for foreign interference during the campaign, especially from China, Russia and Iran.
"We have other countries now that are getting in the mix because they think it works," he said.
"Countries like Cuba, North Korea, Saudi Arabia, we have a lot of countries that are now playing the game."
But the bigger concern is disruption of the count and of reports of the count.
Evanina noted that in 2014 Russian interference compromised the network of the election commission.
"So for me I worry about not up to the election, from the influence perspective, I'm worried about the interference perspective come November 3, 4 and all the way through November," he said.