Last updated June 14, 2017, at 5:50 p.m.

President Donald Trump has dismissed reports about his possible ties to Russia as a "scam" by the media and bitter political opponents.

Yet several investigations — House, Senate and FBI — are already underway into Trump, his associates and their ties to Russia.

The slew of accusations has our heads spinning, so we decided to summarize the big ones here, for our edification and yours. We’ll update if any more significant claims emerge.

A note of caution: Many of these claims are based on interviews other journalists conducted with unnamed sources. We don’t use unnamed sources at PolitiFact, so we couldn’t independently verify their reports.

Claim 1: Putin ordered operatives to influence the U.S. presidential election and sought to elect Trump over Democratic candidate Hillary Clinton.

Evidence: Of the allegations tying Trump to Russia, this one has the most thorough confirmation from the government — notably a Jan. 6, 2017, report out of the Office of the Director of National Intelligence. The report said Putin himself "ordered an influence campaign in 2016 aimed at the U.S. presidential election." Agents also concluded that the Russian government prefered Trump over Clinton, and they intended to undermine Americans’ faith in the electoral system.

Private cybersecurity analysts have said for months that all signs point to Russia.

In the most high-profile example of their election interference, Russian hackers stole emails from the Democratic National Committee and gave them to WikiLeaks. Russian actors also gained access to several states’ electoral agencies. There is no evidence, however, that Russia tampered with vote tallying on Election Day.

Experts also believe that Russia was behind a misinformation and propaganda campaign — such as state-backed Russian media, like RT and Sputnik, pushing exaggerated or false stories that would spread on social media, get picked up by English-speaking conspiratorial websites, and sometimes make it into Trump’s hands.

U.S. government response: Reacting to Russia’s malicious cyber activity during the election, former President Barack Obama imposed new sanctions on Russia in December 2016.

During the campaign and in the weeks following the election, Trump avoided naming Russia as the perpetrator of election-related cyber attacks. But he conceded the point in a pre-inauguration news conference Jan. 11, 2017.

Claim 2: Russia has tried for years to manipulate Trump using lucrative business deals, and Russian operatives have collected compromising information that could potentially be used to blackmail Trump.

Evidence: These allegations are based on a 35-page dossier of opposition research on Trump, prepared by a former British intelligence officer hired by Trump’s Republican and Democratic rivals during the election. The dossier contained numerous explosive but unverified claims.

The man who prepared the original 35-page dossier, Christopher Steele, is respected for his intelligence work, particularly in Russia. However, because the claims remain uncorroborated, they should be viewed with skepticism.

The dossier circulated among Washington lawmakers, intelligence agents and journalists for months before becoming public knowledge, when unnamed U.S. officials told CNN in January 2017 that intelligence officers presented Trump with a summary of the document.

U.S. government response: The FBI is examining ties between Trump’s associates and influential Russians, based in part on the dossier. Trump and others named in the report, including the Russian government, have denied the allegations across the board.

Claim 3: Members of Trump’s inner circle were in contact with Russian intelligence officials throughout the campaign.

Evidence: The primary source for the latest news on this topic is the New York Times, which based its Feb. 14, 2017, report on four unnamed American officials. The officials told New York Times reporters that phone records show Trump associates communicated with senior Russian officials — including Trump’s one-time campaign chair Paul Manafort — but they have not found these calls to be evidence of collusion to disrupt the election.

This New York Times report is the latest and most concrete in a series of similar claims. Russian Deputy Foreign Minister Sergei Ryabkov told a Russian media outlet in November that "there were contacts" with the Trump campaign.

Several Trump associates have done business in Russia. Manafort has long and deep ties to pro-Russian politicians in Ukraine, having worked for Viktor Yanukovych, the country’s pro-Putin former president. Trump’s former campaign foreign policy adviser Carter Page advised Russian gas giant Gazprom, and ousted Trump national security adviser Michael Flynn attended a gala for state media network RT with Putin.

Federal prosecutors have issued grand jury subpoenas to some of Flynn’s associates looking for business records regarding payments Flynn received from Turkey and Russia, according to CNN. House Oversight Committee leaders allege Flynn did not properly disclose those payments, as required by law and Pentagon policy.

U.S. government response: The Trump administration, as well as his associates named in the reports, have denied that they ever communicated with Russian intelligence operatives during the election. Trump also asked the Justice Department to look into the "illegal leaks" to the media about ongoing intelligence investigations.

During June 8 testimony, former FBI Director James Comey said the Feb. 14 New York Times story "was not true." The New York Times stands by its reporting.

Claim 4: Former National Security Adviser Michael Flynn lied about the nature of his conversations with the Russian ambassador, and Attorney General Jeff Sessions didn’t disclose to Congress meetings he had with the ambassador. Trump son-in-law Jared Kushner met with the ambassador, too.

Evidence: The Washington Post reported Feb. 9, 2017, that Flynn privately discussed U.S. sanctions against Russia with Sergey Kislyak, the Russian ambassador to the United States, between Election Day and the inauguration.

Flynn, Vice President Mike Pence and other members of the Trump administration had previously acknowledged that Flynn spoke with Kislyak during the transition period. But they also said Flynn didn’t talk about sanctions during those conversations. This is significant because Flynn possibly lied to the FBI, and he may have violated a law that bans private citizens from negotiating with foreign leaders.

The Washington Post report was based on unnamed sources, but after it came out, Flynn acknowledged that he had "inadvertently briefed the vice president-elect and others with incomplete information regarding my phone calls with the Russian ambassador."

On March 1, the Washington Post reported that Sessions met with Kislyak twice in 2016, once in an informal group setting and later at a one-on-one meeting at Sessions’ former Senate office. Sessions confirmed those meetings to reporters.

Sessions did not disclose his encounters with Kislyak when asked about Trump associates’ contact with Russian officials during his Senate confirmation hearing. He defended his choice not to disclose because he met with the Russian ambassador in his capacity as a senator, not as a Trump campaign surrogate.

Kushner, a White House adviser and husband to Ivanka Trump, has confirmed that he also met with Kislyak in December — as well as Sergey Gorkov, the head of Russian bank Vnesheconombank, which has faced U.S. sanctions over the Russian annexation of Crimea.

U.S. government response: Flynn resigned from his post, after less than a month on the job. Trump called Flynn a "wonderful man" and blamed his resignation on the media, who treated him "very, very unfairly."

Sessions said he would recuse himself from federal investigations into Russia’s possible interference in the presidential election — a move encouraged by both Democrats and Republicans.

Kushner has agreed to discuss these meetings with the Senate Intelligence Committee. The White House has portrayed the meetings as normal diplomatic relations.

Claim 5: Trump associates are pushing for a backchannel deal between Ukraine and Russia.

Evidence: On Feb. 19, 2017, The New York Times reported about three men pushing for a peace deal between Russia and Ukraine: Ukrainian lawmaker Andrii Artemenko, Russian-born Trump business associate Felix Sater, and Trump’s personal lawyer Michael Cohen.

The three men met at a Manhattan hotel in January and have confirmed this account to other journalists. Artemenko said his plan got the stamp of approval from Putin.

Cohen told the New York Times that he delivered a copy of the proposal to Flynn before he resigned, but he has denied that fact to other news outlets. According to the article, Cohen is married to a Ukrainian woman and once worked on an ethanol business there.

U.S. government response: The only White House response so far came from an unnamed administration official, quoted by Business Insider as saying the story is "an absurd attempt to distract" from Trump's activities as president.

Claim 6: Trump has extensive financial ties to Russia.

Evidence: We don’t know the extent of Trump’s business dealings in Russia, in part because he hasn’t released his tax returns. But journalists have pulled together examples of Trump seeking out business opportunities in Russia or with Russian buyers throughout his career.

For example, Trump agreed to host the Miss Universe pageant in Moscow in 2013, a $20 million deal facilitated by Russian real estate mogul and billionaire Aras Agalarov. He also made millions selling a 17-bedroom Florida mansion to a Russian billionaire. His son, Donald Trump Jr., said in a 2008 real estate conference that "Russians make up a pretty disproportionate cross-section of a lot of our assets."

No tangible evidence has turned up that Trump’s business history in Russia controls his actions as president, though some critics have speculated that this is the case.

Trump has not divested from the Trump Organization. A lawyer said the business will not conduct any foreign deals going forward. However, that declaration leaves many loopholes, and the Office of Government Ethics has said Trump’s conflict-of-interest prevention plan is inadequate.

U.S. government response: Trump has said repeatedly that he does not have any potentially problematic business interests in Russia.

"Russia has never tried to use leverage over me. I HAVE NOTHING TO DO WITH RUSSIA - NO DEALS, NO LOANS, NO NOTHING!" he tweeted Jan. 11, 2017.

Lawyers for Trump released a letter May 12 saying Trump does not have any income, debt or investments related to Russia, except for the examples listed above.

Claim 7: Trump fired FBI Director James Comey to curtail the FBI’s investigation into Trump associates’ ties to Russia.

Evidence: The Trump administration’s inconsistent statements, as well as news reports about Comey’s interactions with Trump, are fueling this allegation.

When Trump fired Comey May 9, White House spokespeople, Vice President Mike Pence and Trump himself, in his dismissal letter to Comey, all said he was acting on the recommendation of Deputy Attorney General Rod Rosenstein. Rosenstein wrote a memo recommending that Trump fire Comey because of how he handled the Hillary Clinton email investigation.

But two days later, Trump said he would have fired Comey regardless of Rosenstein’s recommendation, and he had Russia on his mind when he made the decision.

"But regardless of recommendation, I was going to fire Comey knowing there was no good time to do it," he told NBC. "And in fact, when I decided to just do it, I said to myself — I said, you know, this Russia thing with Trump and Russia is a made-up story."

The New York Times reported May 16 that Trump asked Comey to end the FBI’s Flynn investigation, citing a memo Comey wrote about a February meeting with Trump in the Oval Office.

U.S. government response: The White House has emphasized something Acting FBI Director Andrew McCabe told Congress May 11: "There has been no effort to impede our investigation to date."

But McCabe has said he was referring to the impact of Comey’s firing on the investigation, not interference from the White House.

Claim 8: Trump shared highly classified information with Russian diplomats.

Evidence: On May 15, the Washington Post reported that Trump shared top-secret details about an Islamic State threat involving laptops on airplanes with Russian Foreign Minister Sergey Lavrov and Ambassador Sergey Kislyak, during a May 10 Oval Office meeting.

This information is so sensitive, according to media reports, that the United States hasn’t shared it with its allies, much less an adversary like Russia. Trump’s disclosures could jeopardize the United States’ relations with the Middle Eastern partner that procured the intelligence, and it could also put critical intelligence sources in danger.

It’s illegal to improperly disseminate classified information, but presidents are exempt from those laws.

U.S. government response: The White House’s response has shifted since the story broke Monday afternoon, though officials speaking on the record have consistently tried to discredit the reporting.

However, White House officials haven’t explicitly denied that Trump shared classified information with the diplomats, the gravamen of the Washington Post report.