President Barack Obama said in an interview set to air Tuesday night that it's 'possible' Vladimir Putin could be orchestrating a recent computer hack of Democratic National Committee emails in order to help Donald Trump win America's presidential election.

Trump tweeted that the idea was 'crazy,' shortly after Obama's comments surfaced.

Evidence is mounting that hackers aligned with Russia's government were responsible for stealing the DNC's computer files and airing the party's dirty laundry with help from the Wikileaks website.

The public relations damage from messages showing the party trying to sabotage Sen. Bernie Sanders' candidacy has been significant, and led to the resignation on Monday of the party's chairwoman.

Trump was his usual filter-free self on Twitter, writing: 'In order to try and deflect the horror and stupidity of the Wikileaks disaster, the Dem[ocrat]s said maybe it is Russia dealing with Trump. Crazy!'

'For the record,' he wrote in a follow-up tweet, 'I have ZERO investments in Russia.'

Russia's foreign minister Sergei Lavrov sternly dismissed the idea on Tuesday as well.

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Fueling fears: Obama told NBC that he couldn't say for sure what Putin is up to, but left the door wide open for conspiracy theories

Tactical attack: 'What the motives were in terms of the leaks, all that – I can't say directly,' Obama told NBC News. 'What I do know is that Donald Trump has repeatedly expressed admiration for Vladimir Putin.'

President Barack Obama told NBC News' Savannah Guthrie in an interview set for broadcast Tuesday night that it's 'possible' Russian President Vladimir Putin is pulling the strings on the Democratic Party's email hacking scandal in order to help Donald Trump win the November election

Trump isn't impressed with Obama's contention, tweeting that it's a 'crazy' conspiracy theory

Russian fingerprints are all over the DNC hack, computer security experts say, but it's too soon to know whether the prints belong to Putin

At the site of a diplomatic meeting in Laos, reporters asked him about his country's involvement in the controversy.

His only response was 'I do not want to use four-letter words,' according to the Associated Press.

Obama told NBC that he couldn't say for sure what Putin is up to, but left the door wide open for conspiracy theories.

'What the motives were in terms of the leaks, all that – I can't say directly,' Obama told NBC News. 'What I do know is that Donald Trump has repeatedly expressed admiration for Vladimir Putin.'

Hillary Clinton campaign manager Robby Mook claimed Tuesday morning that news reports have established Russians stole Democratic Party documents and emails and 'turned it over to the Wikileaks and other hackers to push out, to harm Secretary Clinton and help Donald Trump.'

That suggestion – that the Russian president fears a Clinton White House more than a Trump administration, would be a powerful argument for the former secretary of state to use in her fall campaign.

'I am basing this on what Mr. Trump himself has said,' Obama added. 'And I think that Trump's gotten pretty favorable coverage back in Russia.'

But a New York Times analysis found that the earliest hacking attempts linked to the current DNC crisis dated back to the middle of 2015, long before Trump became a viable Oval Office hopeful.

Trump's campaign chairman Paul Manafort mocked the allegation on Monday, calling it 'pure obfuscation' and saying Clinton and her handlers 'don't want to talk about what is in the emails.'

Obama administration officials don't believe the Russian government's denials, CBS News reported.

That's because the computer intrusion was similar to others conducted in the past by Russian agents, including distinctive methods that point straight to Moscow.

Hillary Clinton's campaign manager Robby Mook said media reports have established a connection between Russian hackers and the Democratic National Committee leak

'We understand how hack groups use the Internet to attack. The pattern and launch point used before by Russians is similar to the DNC attack,' an intelligence official told CBS.

The AP also quoted Fidelis Cybersecurity expert Michael Buratowski, who said that after an investigation into the hack he was nearly certain that Russians were behind it.

Buratowski cited 'Russian internet addresses, Russian language keyboards, and the time codes corresponding to business hours in Russia, as well as the sophistication of the hack.'

One official told CBS that the Democratic National Committee was given warning ahead of this week's national convention 'that something was going on.' But tthey took some time to respond.'

Another said the Obama administration is basing its conclusions in part on the fact that the hackers 'left all kinds of fingerprints.'

Some of those fingerprints apparently were also left on emails sent to The Hill, an inside-the-beltway Washington, D.C. newspaper, by a hacker who calls himself 'Guccifer 2.0' – the anonymous person who allegedly last week gave 19,000 DNC emails to the Wikileaks website to publish.

The Hill reported Tuesday that emails from the hacker showed signs of being run through an identity-masking technique that operated in the Russian language.

Guccifer 2.0 has denied being a Russian agent, saying he couldn't recognize or read Russian writing.

Virtual Private Networks are standard tools for hackers and other online denizens who want to mask their identities.

By using a VPN to connect to websites – including free email providers – minimally skilled computer users can obliterate evidence of who and where they are.

The website Vocativ reported Tuesday that a commercial data analysis established that when Guccifer 2.0 used an AOL account in France to communicate with reporters in one case, he piggybacked on a VPN that in large part operates in Russian.

The out-of-the-ordinary private French VPN is used by criminals including text-message scammers.

The Hill reported that the website of the VPN, called 'Elite,' is written in Russian. While English translations are available for much of it, some parts of the website – including the entire signup process – are Russian-only.

Guccifer 2.0 has claimed to be Romanian, but in one interview with the computer-expert website Motherboard, he fumbled with the Romanian language and claimed he had no working knowledge of Russian.

Adding to the intrigue, the Elite VPN uses payment services that are popular in Russia. The Hill reported that its website 'also includes a link to a long-defunct Costa Rican payment processor that was seized by law enforcement in 2013.'