Russian and Iran have both obtained US voter information and taken actions to influence public opinion ahead of the 3 November election, Director of National Intelligence John Ratcliffe announced on Wednesday.
Ratcliffe said Iran specifically had sent "spoofed" emails to Americans "designed to intimidate voters, incite social unrest, and damage President Trump."
He said Iran had also distributed a video that implies that people could send in fraudulent ballots, including from outside the United States.
Ratcliffe said both Iran and Russia seek to "to communicate false information to registered voters that they hope will cause confusion, sow chaos, and undermine confidence in American democracy."
"These actions are desperate attempts by desperate adversaries," he said.
The announcement came after registered Democratic voters reported receiving personally addressed emails in the name of the Proud Boys armed militia group, and from an internet domain linked to the Proud Boys.
A number of voters in Florida and other key states in the election battle between Republican President Donald Trump and Democrat Joe Biden said they had gotten the messages.
"You will vote for Trump on election day or we will come after you," the emails said.
"Change your party affiliation to Republican to let us know you received our message and will comply. We will know which candidate you voted for," they said.
"I would take this seriously if I were you," the message ends, adding the voter's address. "Good luck.
Ratcliffe, with FBI Director Christopher Wray beside him, did not explain how the Russians and Iranians had obtained the voter information, or how the Russians might be using it.
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