Washington (CNN) President Donald Trump on Thursday continued to claim millions of people voted illegally in the 2016 election, despite failing to produce evidence to support his repeated assertion.

"In many places the same person in California votes many times," Trump said during a roundtable discussion on tax reform in West Virginia. "They always like to say, 'Oh, that's a conspiracy theory.' It's not a conspiracy theory. Millions and millions of people, and it's very hard because the state guards their records."



California Secretary of State Alex Padilla, a Democrat, responded to Trump's assertion in a statement dismissing the President as "a conspiracy theorist."

"His dishonesty and his rants dishonor the thousands of local elections officials and volunteers who work hard to administer our elections with integrity," the statement said. "Trump was even forced to dissolve his sham election commission, which was a waste of taxpayer dollars and failed to provide a shred of evidence to support his voter fraud lies."

It's far from the first time Trump has made such a claim. After winning the Electoral College but losing the popular vote, Trump claimed that he would have won the popular vote as well "if you deduct the millions of people who voted illegally."

Repeated studies have found no evidence for the claim that widespread voter fraud takes place in the United States, as shown by a collection of research provided by the Brennan Center for Justice at New York University Law School.

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