It was September 2015 when the FBI first noticed that Russian hackers had infiltrated a computer system belonging to the Democratic National Committee.
It was the first sign that Moscow was attempting to meddle in the presidential election.
Nearly a year later, further reporting and testimony from current and former intelligence officials have painted a portrait of Russia's election interference as a multifaceted, well-planned, and coordinated campaign aimed at undermining the backbone of American democracy: free and fair elections.
Key players in Trump-Russia connection allegations
Now, as FBI special counsel Robert Mueller and congressional intelligence committees continue to investigate Russia's election interference, evidence is emerging that the hacking and disinformation campaign waged at the direction of Russian President Vladimir Putin took at least four separate but related paths.
The first involved establishing personal contact with Americans perceived as sympathetic to Moscow — such as former Defense Intelligence Agency chief Michael Flynn, former Trump campaign chairman Paul Manafort, and early Trump foreign-policy adviser Carter Page — and using them as a means to further Russia's foreign-policy goals.
The second involved hacking the Democratic National Committee email servers and then giving the material to WikiLeaks, which leaked the emails in batches throughout the second half of 2016.
The third was to amplify the propaganda value of the leaked emails with a disinformation campaign waged predominantly on Facebook and Twitter, in an effort to use automated bots to spread fake news and pro-Trump agitprop.
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And the fourth was to breach US voting systems in as many as 39 states leading up to the election, in an effort to steal registration data that officials say could be used to target and manipulate voters in future elections.
Intelligence Committee in March, two months before he was fired, that the bureau was investigating Russia's interference in the 2016 election. That probe included an examination of whether the Trump campaign colluded with Moscow to undermine Hillary Clinton, Comey testified at the time.
Restrictions on disclosing classified information in an open setting precluded Comey from naming names; but reports surfaced before he testified that certain members of Trump's campaign had communicated with Russian officials in ways that raised red flags.
Paul Manafort, Michael Flynn, Carter Page, Jared Kushner, and Roger Stone were among those being looked at by federal investigators, reports said, amid the FBI and congressional probes into whether any Trump associates acted as agents of the Kremlin, wittingly or not.
Flynn was forced to resign as national-security adviser in February after it emerged he had discussed US sanctions with Russia's ambassador to the US, Sergey Kislyak, during the transition period. The White House said Flynn resigned because he misled Vice President Mike Pence about his conversation with Kislyak.
It was later reported that the acting attorney general, Sally Yates, had warned the White House in January that Flynn could be vulnerable to Russian blackmail because US intelligence knew Pence had publicly mischaracterized Flynn's interactions with Kislyak.
Paul Manafort, Trump's former campaign chairman, worked to advance Russian interests for over a decade. Beginning in 2004, Manafort served as a top adviser to former Ukrainian President Viktor Yanukovych, a pro-Russian strongman whom Manafort is widely credited with helping win the presidency in 2010. Between 2006 and 2009, Manafort was paid millions to lobby on behalf of Russian billionaire Oleg Deripaska. AP reporter Jeff Horwitz told Fox News that Manafort was "a gun for hire" who was willing to work explicitly "on behalf of Russian interests."
Carter Page, an early foreign-policy adviser to Trump's campaign, has also become a subject of FBI and congressional investigations. His trip to Moscow in July 2016 raised red flags at the FBI, which was granted a warrant by the Foreign Intelligence Surveillance Court to monitor Page's communications on suspicion that he was communicating with Russian officials.
Jared Kushner, Trump's son-in-law and senior adviser, became a subject of the investigation after US intelligence officials intercepted communications suggesting he had proposed setting up a secret backchannel to Moscow using Russian diplomatic facilities on US soil. Kushner met with both Kislyak and Russian banker Sergey Gorkov in December and failed to disclose it on his security-clearance form.
And Roger Stone, a longtime adviser to Trump, communicated with a self-described hacker, Guccifer 2.0, in August 2016 who US intelligence officials believe was a Russian prop.
Former FBI Special Agent Clint Watts told the Senate Intelligence Committee in May that the Trump campaign itself may have been an unwitting agent of Russia.
"Part of the reasons active measures have worked in the US election is because the commander-in-chief has used Russian active measures at times against his opponents," Watts said, pointing to Manafort and Trump's citations of fake-news stories pushed out by Russian-linked entities last year.
"[Trump] denies the intel from the United States about Russia, and he claimed the election could be rigged — that was the number one claim pushed by RT, Sputnik News, all the way up until the election," Watts said. "Part of the reasons Russian active measures work is because they parrot the same lines."
Indeed, the Trump transition team released a statement in December that appeared to cast doubt on the CIA's findings that Russia had meddled in the election with the specific purpose of damaging Clinton's candidacy and swinging voters towards Trump.
"These are the same people that said Saddam Hussein had weapons of mass destruction," the statement said.
The DNC, WikiLeaks, and Guccifer 2.0
In July 2016, the Democratic National Committee announced that Russian hacking groups known as "Cozy Bear" and "Fancy Bear" had infiltrated its servers. The intrusions came after federal investigators warned the DNC in September 2015 that its servers had been breached, but the DNC failed to take action.
After gaining access to the DNC's system in 2016, Fancy Bear and Cozy Bear disseminated thousands of emails via hacker Guccifer 2.0, who leaked the information to WikiLeaks. US intelligence agencies believe Guccifer 2.0 was created by Fancy Bear, or a Russian organization affiliated with the group. WikiLeaks published the first batch of DNC emails on July 22, one day before the Democratic National Convention.
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WikiLeaks founder Julian Assange told Fox News' Sean Hannity during a January interview that the Russian government did not provide the hacked DNC emails to him. But US intelligence agencies believe WikiLeaks has become a Kremlin propaganda tool.
Cybersecurity experts at the intelligence firm ThreatConnect also linked Guccifer 2.0 back to Russia and concluded the hacker was the product of a Russian disinformation campaign. The New York Times reported in December that Guccifer 2.0 had also hacked into the Democratic Congressional Campaign Committee and released the information to reporters covering competitive House districts.
A little over two months later, on October 7, WikiLeaks released a batch of emails from Clinton campaign manager John Podesta's account. The hack of Podesta's emails came after Trump confidant Roger Stone tweeted in August, "Trust me, it will soon the [sic] Podesta's time in the barrel. #CrookedHillary"
WikiLeaks continued releasing Podesta's emails and published nearly 60,000 messages leading up to Election Day. Podesta said after the initial breach that Russian intelligence was responsible.
Hollis Johnson"A big difference to me in the past was, while there was cyberactivity, we never saw in previous presidential elections information being published on such a massive scale that had been illegally removed both from private individuals as well as organizations associated with the democratic process both inside the government and outside the government," Adm. Mike Rogers, the director of the National Security Agency, told the House Intelligence Committee in March.
It soon emerged that Russian hackers had also accessed the Republican National Committee's servers and accounts belonging to Republican officials, but had chosen not to release the information. This development appeared to confirm intelligence findings that Russian meddling was done specifically to hurt Clinton and aid Trump.
The US intelligence community "is confident that the Russian Government directed the recent compromises of e-mails from US persons and institutions, including from US political organizations," Director of National Intelligence James Clapper and the Department of Homeland Security said in a joint statement shortly after the first batch of Podesta's emails were first leaked.
During a January hearing before the Senate Armed Services Committee with other intelligence chiefs, Clapper reaffirmed that finding. "We stand more resolutely on that statement," he said.
Fake news, trolls, botnets
In early January, the Office of the Director of National Intelligence released a declassified report documenting the results of the investigation former President Barack Obama had requested into Russian election interference.
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The report said that while Russian operatives did not change vote tallies, Russian President Vladimir Putin had ordered an elaborate effort to propel Trump to the presidency — not only via hacking but also through the dissemination of "fake news" aimed at undermining Clinton and boosting Trump.
The Russians, Comey said in March, were also "unusually loud" in their intervention, leaving digital footprints on the DNC and John Podesta email hacks that were sloppy and easily linked back to the Kremlin.
Meanwhile, state-sponsored Russian news agencies like RT and Sputnik, openly backed Trump. And automated Twitter accounts — many of them linked to Russia and aided by professional trolls paid by the Kremlin — flooded the social-media platform with pro-Trump rhetoric and made-up news throughout the campaign and especially in the days leading up to the election.
Russian internet trolls — paid by the Kremlin to spread false information on the internet — have been behind a number of "highly coordinated campaigns" to deceive the American public, journalist Adrian Chen found when researching Russian troll factories in St. Petersburg in 2015.
It's a brand of information warfare, known as "dezinformatsiya," that has been used by the Russians since at least the Cold War. The disinformation campaigns are only one "active measure" tool used by Russian intelligence to "sow discord among," and within, nations perceived as hostile to Russia.
From his interviews with former trolls employed by Russia, Chen gathered that the point of their jobs "was to weave propaganda seamlessly into what appeared to be the nonpolitical musings of an everyday person.
"Russia's information war might be thought of as the biggest trolling operation in history," Chen wrote. "And its target is nothing less than the utility of the Internet as a democratic space."
In a telling case study of how widespread and pervasive fake news was during the election, Oxford University researchers found that nearly half of the news Michigan voters were exposed to on Twitter leading up to Election Day was fake. They found that the proportion of "professional to junk news" was "roughly one-to-one," and that "fully 46.5% of all content presented as news" about politics and the election fell under "the definition of propaganda" when unverified WikiLeaks content and Russian-origin news stories were factored in.
As many as 39 state-election systems targeted
In January, President-elect Trump issued a statement after he was briefed on the intelligence community's classified report on Russia's election interference.
"While Russia, China, other countries, outside groups and people are consistently trying to break through the cyber infrastructure of our governmental institutions, businesses and organizations including the Democrat [sic] National Committee, there was absolutely no effect on the outcome of the election including the fact that there was no tampering whatsoever with voting machines."
As it turns out, that was not entirely true.
Bloomberg reported in June that election systems in as many as 39 states could have been attacked, though voting tallies are not believed to have been altered or manipulated in any way.
"In Illinois, investigators found evidence that cyber intruders tried to delete or alter voter data," Bloomberg said. "The hackers accessed software designed to be used by poll workers on Election Day, and in at least one state accessed a campaign finance database."
The report was bolstered by a leaked NSA document published by The Intercept earlier this month detailing how hackers connected to Russian military intelligence had attempted to breach US voting systems days before the election.
National-security experts were floored by the document and said it was the clearest evidence so far that Russia interfered in the election.
Department of Homeland Security official Jeanette Manfra confirmed to the Senate Intelligence Committee on June 21 that Russian hackers targeted at least 21 states' election systems in 2016, successfully exploiting a small number of networks and stealing voter registration data. Time reported on Thursday that the hackers successfully altered voter information in at least one election database and stole thousands of voter records containing private information like Social Security numbers.
The exposure of that data has left upcoming elections vulnerable to manipulation. Virginia and New Jersey will hold gubernatorial elections later this year, and all 435 seats in the House and 33 of the 100 seats in the Senate will be contested in the 2018 midterm elections.
Putin has consistently denied the Kremlin had anything to do with the hacking or disinformation campaigns waged in 2016 to bolster Trump and hurt Clinton. But he acknowledged a potential Russian role for the first time earlier this month when he said that "patriotically minded" Russian citizens might have taken it upon themselves "to fight against those who say bad things about Russia."