An American news anchor has expertly laid out how Donald Trump's rhetoric has heightened the threat of violence at his campaign events.
Rachel Maddow uses footage of previous events to draw a link between the billionaire's words and the hostility which saw a Tump rally cancelled on Friday.
The MSNBC host said: "If you want me to prove to you it was deliberate what happened tonight in Chicago, here's where it came from."
Watch Maddow explain the timeline, above. Here are some key highlights:
1 February: 'I will pay for the legal fees'
On 1 February, Donald Trump told a rally in Cedar Rapids: "If you see somebody getting ready to throw a tomato, knock the crap out of them would you, seriously?
"I promise you, I will pay for the legal fees."
22 February: 'They'd be carried out on a stretcher'
After a protester attempted to disrupt his speech, Trump told a rally in Las Vegas: "I loved the old days, you know what they'd do to guys like that in a place like this? They'd be carried out on a stretcher.
"I'd like to punch him in the face, I tell you."
26 February: 'They'd rip him out of that seat'
Responding to a similar protest in Oklahoma City, Trump said: "I loved the old days, they'd rip him out of that seat so fast but today everybody's politically correct.
"I think go to hell with being politically correct."
29 February: 'Are you from Mexico?'
Trump berated protesters in Radford, Virginia, heckling: "Are you from Mexico? Are you from Mexico?"
He earlier ordered aides: "Get them out of here."
4 March: 'I'll defend you in court'
Trump rejoiced in the hostile atmosphere of his Warren, Michigan rally, saying: "Oh, this is amazing. It's so much fun, I love it, I love it.
"We having a good time? U-S-A, U-S-A."
Later he said of protestors: "Yeah, get 'em out, try not to hurt 'em. If you do I'll defend you in court, don't worry about it."
10 March: 'They used to treat them very, very rough'
As the audience jostled with protestors in Fayetteville, North Carolina, Trump recalled: "We had some guys punching back, it was a beautiful thing. They started punching back.
"In the good old days [disruption] doesn't happen because they used to treat them very, very rough.
"And when they protested once they would not do it again so easily.
"But today they walk in, put their hand up and put the wrong finger in the air and they get away with murder, because we've become weak.
12 March: 'Nobody wants to hurt each other anymore'
Just hours before his Chicago rally was cancelled, Trump told an audience in St Louis: "Part of the problem is nobody wants to hurt each other anymore.
"They're being politically correct at the way they're taking them out.
"Protestors are realising there are no consequences for protesting any more.
"Our country has to toughen up folks, we have to toughen up.
"These people are so bad for our country you have no idea.
"They can raise their bad finger up in the air and drive people which is very unfair and... when they get a little overly angry they get in trouble.
"The guy that raised his finger? He's not in trouble."
Friday's Chicago event was due to begin at 6pm local time at the University of Illinois, but was axed 30 minutes after the scheduled start time after thousands of anti-Trump protesters packed the free event.
On Wednesday, a Trump supporter was arrested after sucker-punching a protestor at a rally.
The billionaire property tycoon has confirmed he has since instructed aides to consider helping the man with his legal costs.
On Saturday, Trump appeared to blame supporters of Democratic candidate Bernie Sanders for the protests. "Get your people in line, Bernie," Trump said.
He continues to lead the race for Republican nomination, according to the latest opinion polls.