Donald Trump supporters and protesters have clashed again following a rally that the Republican presidential frontrunner held in Cleveland, Ohio as he blamed Democrat Senator Bernie Sanders for escalating chaos.

US police also fired pepper spray against an unruly crowd of demonstrators outside Trump's rally in Kansas City on Saturday.

"Bernie's People," Trump repeatedly said in Cleveland, referring to several demonstrators before having them escorted out of the venue.

The crowds later faced off outside, arguing about immigration and racism, before they were broken up by law enforcement.

The Donald Trump show - The Listening Post

"I'm terrified by Donald Trump, by the way I see his supporters behaving, by the things he says about women, people of colour, anyone that's different to him," said Ben Bowman, a Trump protester.

At the rally, Trump also referred to "Bernie our communist friend" and called him a "lousy" senator while blaming him for the disruptions at his rallies.

Rosa Rossi, a Trump supporter, said she thinks the former reality TV show star can revive the US' past standing in world affairs.

"I believe he can get the illegal immigrants in control, he can build a wall, and he can also make better deals for America, where America will rise and be the most powerful country in the world again," Rossi said.

In a Twitter post late Saturday, Kansas City police said they used pepper spray twice outside a rally adding two people were arrested. It wasn't clear if those sprayed were demonstrators or Trump supporters.

Videos posted on Twitter showed a large number of people being sprayed during the incident.

As you can see, we were far from what happened and were not involved but he in walked up spraying us pic.twitter.com/f22WB5FAAG — Chris (@stokith) March 13, 2016

Trump has both inspired impassioned supporters and ignited a backlash of angry dissent with his promise to build a wall along the US-Mexican border to keep out illegal immigrants, and his call to temporarily ban the entry of non-US Muslims into the country.

Trump's events have been intense. For months, he incorporated interruptions by protesters into his speeches, growling "Get 'em out!" - sparking explosive cheers from the audiences as he did so.

But the confrontations began to escalate this month, most notably at a Trump event in New Orleans. A steady stream of demonstrators interrupted Trump's speech, including a huddle of Black Lives Matter activists, who locked arms and challenged security officials to remove them.

READ MORE: US election - Trump cancels Chicago rally after scuffles

There were skirmishes throughout the speech, mostly pushing and shoving, although one man was captured on video biting someone.

Chicago violence

Hours before Trump was scheduled to appear on Friday night at the University of Illinois at Chicago, the atmosphere inside a campus arena was crackling as protesters and supporters shouted back and forth, arms raised and yelling in each other's faces.

Some of the protesters, many of whom said they supported Democratic candidate Sanders, said they planned to rush the stage when Trump came out to speak. They didn't get the chance as Trump called off the rally before even getting to the venue.

READ MORE: US election snapshot - inside a Donald Trump rally

On Saturday morning, Trump was mid-speech when a man, later identified by authorities as Thomas Dimassimo of Fairborn, Ohio, jumped a barricade and rushed at Trump. He was able to touch the stage before he was tackled by security officials.

Trump initially laughed it off but later in the day he said Dimassimo had ties to the Islamic State of Iraq and the Levant (ISIL, also known as ISIS).

Experts who watched a video that Trump tweeted as evidence called the allegation "utterly farcical".

"Trump's accusations about it being linked to ISIS serve only to underline the totality of his ignorance on this issue," said Charles Lister, a fellow at the Middle East Institute.

Democratic frontrunner Hillary Clinton called Trump's rhetoric "political arson". She said Trump's "ugly, divisive rhetoric" and alleged encouragement of violence "is wrong, and it's dangerous".