Washington(CNN) Congressional Democrats' request to the FBI to brief lawmakers on foreign election interference included concerns about a Russian-linked "disinformation" campaign to target former Vice President Joe Biden in the 2020 election, according to a source familiar with the matter.
House Speaker Nancy Pelosi, Senate Minority Leader Chuck Schumer and the top Democrats on the House and Senate Intelligence committees sent FBI Director Chris Wray a letter last week urging a briefing for all lawmakers on a foreign interference campaign that "seeks to launder and amplify disinformation."
The lawmakers did not detail specifics in the letter to Wray, which was released publicly on Monday. But a classified addendum sent to the FBI included concerns about a potential Russian campaign targeting Biden, the source said, including that information from entities with ties to Russia was being provided to Senate Homeland Security Chairman Ron Johnson, R-Wisconsin, who is leading an investigation into Biden, his son Hunter Biden and Ukrainian energy firm Burisma.
The material the Democrats referenced was included in warnings that the FBI has been offering for months now about election interference, another source said.
The Democrats' letter comes as the 2020 campaign between Biden and President Donald Trump is heating up and Democrats on guard for a repeat of 2016, when Russia interfered in the presidential election to benefit Trump. Shortly after the Democrats' released their letter Monday, Biden's campaign issued a statement saying if elected, he would "treat foreign interference in our election as an adversarial act that significantly affects the relationship between the United States and the interfering nation's government."
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Democrats did not reach out to their Republican counterparts to sign onto the letter, according to a source. Acting Senate Intelligence Chairman Marco Rubio said Tuesday he was not asked to join it.
Politico first reported Democrats' concerns about Russia and Johnson's committee.
Johnson told reporters Tuesday he wasn't aware of any Russia disinformation sent to his committee, but said that his staff vets any evidence the panel is provided and takes anything coming from Ukraine with a "huge grain of salt."
"I'm not aware of every piece of information our committee has gathered. We're encouraging people to send us information, but then we fully vet it," Johnson said. "We take everything with a grain of salt we get from Ukraine. I think you have to."
Johnson charged that it was Democrats who were peddling Russian disinformation through the opposition research dossier compiled by Christopher Steele, pointing to recently declassified footnotes that showed the intelligence community raised concerns in 2017 Steele's dossier could have included Russian disinformation. "We're being accused of being used as a tool of Russia. The tool of Russian disinformation was in the Steele report," he said.
Johnson spokesman Austin Altenburg said that claims Russian disinformation had been provided to the committee were false. He said committee staff had been briefed by the FBI on the issue and that Johnson had requested a member briefing too. "It does a disservice to our election security efforts when Democrats use the threat of Russian disinformation as a weapon to cast doubt on investigations they don't like but are silent when recently declassified intelligence revealed that Democrat-funded opposition research on the Trump campaign contained actual Russian disinformation," Altenburg said.
In recent months, a small group of Ukrainian political figures has injected themselves into the 2020 US presidential election by releasing and promoting alleged audiotapes of Biden. Some of these figures are connected to Kremlin interests or to Russian intelligence agencies, which experts say suggests their actions may be part of a Russian-backed misinformation campaign.
The recordings are of Biden's dealings with former Ukrainian President Petro Poroshenko, and they appear authentic. But the material reinforces Biden's claims that he promoted US interests and didn't do anything improper in Ukraine. There is no proof of wrongdoing on the tapes, and the Biden campaign maintains that these releases are blatant Russian meddling against Biden.
Some Republicans and right-wing news outlets have embraced the baseless claims being levied by these controversial Ukrainian figures. Some of these figures, including Ukrainian lawmaker Andrii Derkach, have worked closely with Trump lawyer Rudy Giuliani. Johnson has tried to secure testimony from another Ukrainian in this orbit, former diplomat Andrii Telizhenko.
Many of these false narratives played a central role in Trump's impeachment proceedings. At that time, Fiona Hill, who was Trump's top adviser on Russia, testified that some Republicans were promoting a "fictional narrative" that was concocted by Russian intelligence agencies, and were thus peddling "politically derivative falsehoods that so clearly advance Russian interests."
Publicly, Democrats were vague about their concerns on Tuesday, while reiterating their desire for all lawmakers to hear from the FBI.
"I'm concerned about all the members of Congress and everyone being targeted by a foreign country," Pelosi told CNN when asked if she was specifically concerned about an effort targeting Biden.
House Intelligence Chairman Adam Schiff told CNN the FBI was still "considering" the request for a briefing, but had not yet made a final decision. He argued it was important for lawmakers to hear from the FBI directly.
"There may be ways for us to disseminate the information among our members in terms of what the committee possesses, but regardless, I think it would be advantageous for the director of the FBI to come and brief all the members so they can answer questions," Schiff said.
Sen. Mark Warner, the top Democrat on the Senate Intelligence Committee, said of the letter Monday: "I've been raising concerns about election security for months on end, and I think it's very important that all senators be briefed ... I've had these concerns virtually since the end of the '18 cycle."
On CNN's "New Day" Tuesday, Schumer said that a "lot of countries" were trying to interfere, adding, "we have to be prepared."
US officials have been warning about interference from a number of countries, including Russia. Gen. Paul Nakasone, the top official at both the National Security Agency and US Cyber Command, said Monday the US is seeing a "rise in capacity" and "capability" of cyber programs from foreign adversaries, including Russia, China, North Korea and Iran.
"Our No. 1 goal, our No. 1 objective at the National Security Agency and US Cyber Command, is a safe, secure and legitimate 2020 elections," Nakasone added.
Rubio declined to comment specifically on the letter, while noting that foreign election interference continues to be a problem.
"We should expect that multiple counties will try to conduct informational warfare and influence campaign, policy, public discourse, for the foreseeable future," he said. "It's not a new problem but it's a growing one."