Republican presidential frontrunner Donald Trump on Sunday threatened to send his supporters to disrupt Sen. Bernie Sanders’ (I-Vt.) campaign rallies.

The threat came a day after Trump blamed Sanders for mass protests that led the Republican candidate to cancel a Friday rally in Chicago. Speaking in Cleveland on Saturday, Trump called on Sanders to “get your people in line.”

Though published reports indicate that some of those protesting Trump in Chicago were Sanders supporters, the Vermont senator said in a written statement Saturday that his campaign “did not organize the protests.” In the same statement, Sanders called Trump a “pathological liar.”

Writing on Twitter Sunday morning, Trump further escalated the rhetoric.

“Bernie Sanders is lying when he says his disruptors aren’t told to go to my events,” Trump wrote. “Be careful Bernie, or my supporters will go to yours!”

On CNN’s “State of the Union” Sunday, host Jake Tapper told Trump that his Sanders tweet “sounds like a threat … It sounds like making things, perhaps, worse.”

“No, it’s not a threat. It’s not a threat. It’s not a threat at all,” Trump responded.

The New York businessman elaborated by saying that he and his supporters were subject to a double standard — and that if they interrupted a Sanders rally “they would be arrested and all sorts of things would happen to them.”

Speaking later on the CNN show, Sanders again distanced himself from the Trump protests, saying that he played no role in them and that Trump “cannot stop lying about anything.”

He condemned the tone of Trump’s campaign.

“I mean, this is a campaign whose rhetoric, whose people now, because I think of that rhetoric, are leaning too much in the direction of violence,” Sanders said. “And Trump himself, I think, is the primary cause of this. He has absolutely got to tone it down.”