Democratic presidential candidate and Vermont Sen. Bernie Sanders appeared on ABC’s “This Week” Sunday morning to discuss allegations that he organized protesters for Friday’s would-be Trump rally in Chicago.

Sanders called the accusations “totally untrue.”

Image via Twitter/This Week

Image via Twitter/This Week

“I think anybody understands Mr. Trump’s campaign knows that he tells the truth very very rarely,” he said. “And I’m afraid that on this occasion he’s lying again.”

After Trump cancelled the Friday rally amidst an onslaught of violent protests, the Republican front-runner took to Twitter and voiced his suspicions that Hillary Clinton and Sanders’ people were behind the upset:

Two days later Trump reasserted his claims on Twitter and during an interview on “Fox News Sunday”:

“We have millions of supporters out there,” Sanders said Sunday. “Many of them were at that rally, along with many many other protestors. But to say that we organized that — totally untrue.”

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