Iran

Updated at 8:33 p.m. ET

Iranian influence specialists are behind threatening emails sent to voters in Alaska and Florida, U.S. officials said on Wednesday evening and suggested that more such interference could be in store from Russia.

Director of National Intelligence John Ratcliffe said the U.S. intelligence community believes Iranian and Russian operatives obtained voter-record information, which enabled Iran to target some people with intimidating emails based on party registration about how they'd better vote for President Trump "or else."

Updated at 4:39 p.m. ET

Authorities in government and Big Tech unveiled a number of actions and announcements on Thursday in the ongoing effort to defend the 2020 election from foreign interference.

The Treasury Department announced it's sanctioning a member of the Ukrainian parliament who waged an influence campaign aimed at the 2020 election — one who specifically spread "false and unsubstantiated narratives" about former Vice President Joe Biden.

A Department of Homeland Security official said in a whistleblower complaint that the head of DHS told him to stop reporting on the Russian threat to the U.S. election because it "made President Trump look bad."

The White House and DHS denied the allegations. However, the president's Democratic critics say the accusations are the latest sign that the Trump administration is attempting to politicize the intelligence community and downplay Russian attempts to interfere in this year's election, as Moscow did in 2016.

Google, Facebook, Twitter and other major tech companies met with U.S. government officials on Wednesday to discuss their plans to counter disinformation on social media in the run-up to the November election.

Updated at 7:10 p.m. ET

The top counterintelligence official in the U.S. government warned Friday of ongoing interference and influence efforts by China, Russia and Iran.

William Evanina, who leads the National Counterintelligence and Security Center, said that the U.S. government has assessed that China prefers President Trump losing the election, because Beijing considers him "unpredictable," while Russia is working to undermine Democrat Joe Biden.

Threats to U.S. elections this year could be broader and more diverse than before, warns the spy world's boss for election security — and she also acknowledged the limits of her ability to tackle them.

Shelby Pierson, the intelligence community's election threats executive, told NPR in an exclusive interview that more nations may attempt more types of interference in the United States given the extensive lessons that have since been drawn about the Russian attack on the 2016 presidential election.

Federal prosecutors say a Columbus man charged with defying U.S. trade sanctions by illegally exporting gas and oil pipeline parts to Iran has been sentenced to 20 months in federal prison.