President-Elect Donald Trump claimed on Sunday that millions of votes were illegally cast in the 2016 election while offering no evidence to support his claim.

Responding to the ongoing effort to recount votes in Wisconsin, as well as to Democrats’ emphasis of the fact that Hillary Clinton won more votes on November 8th, the president-elect asserted that he actually did win the popular vote.

In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally — Donald J. Trump (@realDonaldTrump) November 27, 2016

It would have been much easier for me to win the so-called popular vote than the Electoral College in that I would only campaign in 3 or 4– — Donald J. Trump (@realDonaldTrump) November 27, 2016

states instead of the 15 states that I visited. I would have won even more easily and convincingly (but smaller states are forgotten)! — Donald J. Trump (@realDonaldTrump) November 27, 2016

The idea that Trump could have still won the election if it were based solely on the popular vote is a reasonable point that the president-elect has made before. But this is the first time he has actually alleged that not only did voter fraud take place in the election, but it took place on an extremely large scale. To believe that Trump won the popular vote on November 8th, one would have to accept that over two million ballots were fraudulent.

There has not been any credible evidence that widespread voter fraud took place this year. It’s possible that Trump is referring to a story spread by conspiracy theorists like Alex Jones – a man who believes that September 11th was an inside job and that the Sandy Hook shooting was a false flag operation – that three million votes were cast by undocumented immigrants in the 2016 election. That claim has been spread around fringe websites but has never been verified; as pointed out by Snopes, the report originated from a random Twitter account belonging to a user claiming to be a voter fraud expert but who offers no evidence whatsoever. He has repeatedly declined to share his data or his sources when questioned by journalists.

@tynanwrites @TrueTheVote No. We will release it in open form to the American people. We won't allow the media to spin this first. Sorry. — Gregg Phillips (@JumpVote) November 15, 2016

This comes hours after Donald Trump mocked Hillary Clinton for not accepting the result of the 2016 election by participating in a recount effort.

The Democrats, when they incorrectly thought they were going to win, asked that the election night tabulation be accepted. Not so anymore! — Donald J. Trump (@realDonaldTrump) November 27, 2016

Hillary Clinton conceded the election when she called me just prior to the victory speech and after the results were in. Nothing will change — Donald J. Trump (@realDonaldTrump) November 27, 2016

Nearly four hours after the original tweet, Trump continued to question the result of the election, making the claim – once again without evidence – that serious voter fraud took place in Virginia, New Hampshire and California. Hillary Clinton won all three of those states.

Serious voter fraud in Virginia, New Hampshire and California – so why isn't the media reporting on this? Serious bias – big problem! — Donald J. Trump (@realDonaldTrump) November 28, 2016

Officials from Virginia, New Hampshire and California have released statements saying that no voter fraud took place in their states. First, Virginia Department of Elections Commissioner Edgardo Cortés told Politico, “The claims of voter fraud in Virginia during the November 8 election are unfounded. The election was fair and all votes cast by eligible voters were accurately counted.”

Then, New Hampshire Deputy Secretary of State David Scanlan told NBC News, “This is not the first time that there have been claims like that made about New Hampshire elections. We don’t have any evidence, and there has been nothing filed with our office or the Attorney General’s office that there’s widespread voter fraud in New Hampshire.”

Finally, California Secretary of State Alex Padilla released a statement on Twitter saying that Trump’s claims are unsubstantiated and absurd.