
Anti-Donald Trump protests turned into skirmishes with police in Phoenix on Tuesday, as cops unloaded on the crowds gathered outside his rally with tear gas.

In one wince-inducing moment screened on CBS5 and captured on Twitter, one protester - clad in a gas mask - kicked a canister of tear gas back at police.

Seconds later a cloud of dust mushroomed up from his groin and he doubled up in agony.

'A guy just got shot with a rubber bullet,' remarked one host, as the other lapsed into a pained silence. It has since emerged the man was hit with a tear gas canister.

'So... er... yeah, the officers are not, are not messing around at all,' the host stuttered as the stricken protester was dragged away by an ally.

He was just one of many caught up in the post-rally violence, as cops used nonlethal methods to disperse crowds who had thrown rocks and bottles at them.

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An anti-Trump protester was filmed kicking a tear gas canister (both pictured left) towards police after a Trump rally in Phoenix on Tuesday. He was then shot in the groin (right)

Newsreaders said he had been hit by a rubber bullet as he collapsed in agony, and was later helped to his feet and taken away by a friend. It has since emerged he was hit with a tear gas canister

The violent scenes came after police tried to disperse crowds of anti-Trump protesters with tear gas following the rally. The anti-Trump crowd were vastly outnumbered by Trump fans

Police fired pepper spray to disperse protesters outside a rally by U.S. President Donald Trump in Phoenix, Arizona

Protester kicks tear gas back at police. Police shoot him with a rubber bullet on live TV. VIDEO: pic.twitter.com/5qyHDZlpNF — Tim Ring (@timringTV) August 23, 2017

The unrest broke out after Trump swung through the city for a rally designed to fire up his base - which it did, his fans vastly outnumbering anti-Trump protesters.

Supporters and opponents alike gathered in the 107-degree heat, but it was only after the rally that violence broke out.

Police say that protesters threw water bottles and rocks at their lines, causing them to respond in kind with tear gas, pepper spray, rubber bullets and pepper balls.

Clouds of the gas filled the night air as the president's supporters began leaving the downtown Phoenix Convention Center.

At around 11:20pm, Phoenix Police Chief Jeri Williams said that three people had been arrested on charges related to the protest.

She added that one person was arrested on an unrelated warrant, and that two officers were treated for heat exhaustion.

Police have not given an estimate of the number of protesters, but Arizona media said there were several thousand

Four people were arrested during the protest, Phoenix Police Chief Jeri Williams later said during a news conference

The unrest broke out after Trump swung through the city for a rally designed to fire up his base. Pictured: Police prepare to advance on protesters

Supporters and opponents alike gathered in the 107-degree heat, but it was only after the rally that violence broke out

Police say that protesters threw water bottles and rocks at their lines, causing them to respond in kind with tear gas

A haze enveloped the night sky as protesters and police clashed outside the convention centre where the president had just wrapped up his speech

Police were seen with riot shields and tear gas guns, and reportedly used rubber bullets and pepper balls on the crowds

Several protesters were seen leaving the scene with tears streaming down their faces, using water to wash the painful chemicals from their eyes

A contingent of protesters stayed behind after the clash with police had ended. Their numbers were small.

Trump beat Hillary Clinton in Nevada by a tenuous 3.5 percentage points last year, and is now polling 7 points lower there than his election total.

So his visit on Tuesday was apparently an attempt to boost that falling number.

In contrast with Monday's calm, measured speech about the prolonged war effort in Afghanistan, Tuesday night's Trump performance was a raucous affair akin to the campaign events that forced America's election prognosticators to rewrite every political rule book.

The president's first audience members began arriving 10 hours before the rally's appointed starting time, standing in Phoenix's concrete city center in temperatures that reached 107 degrees.

Mr Trump had opened his political rally with calls for unity and an assertion that 'our movement is about love', but he then erupted in anger

He blamed the media for widespread condemnation of his response to deadly violence at a white supremacists' protest in Charlottesville, Virginia, and shouted that he had 'openly called for healing, unity and love' after the tragedy

Protesters outside the Phoenix event fled the scene coughing as an officer in a helicopter used a speaker to urge them to leave the area

The Phoenix Fire Department said it treated 56 people for heat exhaustion and dehydration at the convention center, while twelve people were taken to the hospital

President Donald Trump swung through Phoenix on Tuesday for a campaign rally designed to fire up his base in a state where he beat Hillary Clinton by 3.5 percentage points last year. Trump (right) and Vice President Mike Pence deplane Air Force One in Phoenix on Tuesday

Arizona's Republican governor Doug Ducey (left) greeted Trump at the Phoenix airport but he did not attend the evening rally

Police separate protesters from a line of Trump rally-goers that stretched six city blocks before the campaign rally outside the Phoenix Convention Center

Pro-Trump activists gave as good as they got, cheering for Trump and shouting back at his detractors

Two-dollar cold water bottles outsold three-dollar tacos on street corners. Trump fans took turns holding each other's places in line for bathroom breaks and visits to a cool spray mist descending from a nearby Hyatt hotel's entryway overhang.

The most common sight, other than 'Make America Great Again' hats, was umbrella after umbrella sticking up above the crowd – not to protect against much-needed rain, but used as a parasol to tame the heat.

The heat took its toll, too, on a promised mass-protest that threatened to bring thousands who stayed home.

A combined 7,400 people had indicated that they plan to show their disgust for the president, via RSVPs on two Facebook advertisements for anti-Trump rallies.

Only about 500 showed up, and found pro-Trump activists creating just as much noise. They shouted 'Walk of shame!' in response as the rally-goers made their way to the front of a line that snaked for six city blocks.

An hour before Trump was scheduled to speak, there were an estimated 8,000 inside the convention center.

The anti-Trump protesters were energetic and loud, but far outnumbered and kept at bay by police

Some 7,400 people had indicated that they plan to show their disgust for the president, via RSVPs on two Facebook advertisements for anti-Trump rallies, but only about 500 showed up to protest. Anti-Trump protesters inflate a balloon depicting Trump as a KKK member

One protester outside patrolled back and forth, parading a sign before news cameras that read: 'Looks like we've taken this 'Anyone can grow up to be president' thing just a bit too far.'

Another carried a First Amendment message: 'It's only 'Fake News' if he doesn't like it. Support freedom of the press!'

One small group inflated a 20-foot-tall Trump effigy dressed as a Ku Klux Klan member.

On the other side of a police-patrolled barricade stood a man in a T-shirt proclaiming that 'AntiFa is Satan,' a reference to leftist 'Anti-Fascist' protesters who wear black masks and carry mace and clubs.

He held signs denigrating both the Black Lives Matter movement and the Muslim faith.

'BLM are racist thugs,' one read. The other, which included the Muslim crescent with a red line through it, said that 'Every real Muslim is a jihadist!'

At its peak the left-wing protest crowd reached into the hundreds, a far cry from the thousands expected by organizers who collected RSVPs on Facebook

Behind him stood Trump supporter Ray Martinez in a campaign t-shirt bearing an unusual tagline: 'TRUMP 2016: F**k your feelings.'

He held a sign aloft as a warning to anti-Trump activists: 'Don't start no s**t, won't be no s**t.'

A woman in the protest crowd was heard yelling, 'F**k you racist!' over and over again.

Trump has spoken at the Phoenix Convention Center before, a late-October 2016 rally where his establishment-rattling immigration message was temporarily overshadowed by a fan who appeared to chant 'Jew-S-A' at reporters as he left the venue.

The man, George Lindell, later claimed he was misunderstood.

'When you pronounce 'USA' in Spanish it sounds like 'Jew S. A.',' Lindell said, adding: 'We need to integrate the Spanish lingo, the Spanish language into our society.'

An anti-Trump protester holds a sign outside the Phoenix Convention Center

Trump's return to Phoenix on Tuesday came with its own newer set of controversies.

The White House diffused the most explosive one by telling reporters aboard Air Force One that there would be no announcement of a presidential pardon for embattled former sheriff Joe Arpaio, a Trump endorser who faces a possible prison term for defying a judge's order related to illegal immigration in 2011.

'There will be no discussion of that today at any point, and no action will be taken on that front at any point today,' White House spokeswoman Sarah Huckabee Sanders said.

Trump's Arizona swing started with a reminder of his laser focus on illegal immigration, visiting with Yuma, Arizona-based Marines who work with U.S. Border Patrol agents and inspecting a Predator drone that they use to patrol the border U.S. with Mexico.

Administration officials who briefed reporters on Tuesday pointed to a fortified border fence along the section of border nearest to Yuma, and said it was largely responsible for a dramatic drop in people illegally making it from Mexico to the United States.

The president started his Arizona swing in Yuma, meeting with U.S. border Patrol agents and inspecting the hardware they use to fight illegal immigration and human trafficking

Southern Arizona Militia, a private group (left), stood guard outside the Phoenix Convention Center before the rally for Trump. Separately, a left-wing group called the John Brown Gun Club (right) brought its own armed watchdogs

That number was down 46 per cent in the first seven months of 2017, compared to 2016.

The fence has been up since 2008, however, and numbers have been steadily decreasing since at least 2005.

Republican partisans and Trump himself have suggested that his election victory by itself signaled a coming change in policy that made human traffickers re-think their strategies.

Yet the president missed a chance to pose in front of the imposing border barrier that was just 15 miles away from his stop in Yuma, with one administration official blaming unspecified 'security concerns.'

Trump's visit to Arizona brought the state's sometimes smashmouth GOP politics to a head since there is no love lost between Trump and Arizona's two U.S. senators, both Republicans.

Sen. Jeff Flake faces a stiff primary challenge next year from former state lawmaker Kelli Ward, whom Trump has cheered on Twitter as he called Flake 'WEAK on borders' and 'toxic' in the Senate.

Trump has battled with arizona Republican Senator Jeff Flake, who was among the 'Gang of Eight' who proposed in 2013 giving legal status to millions of illegal immigrants

Trump called Flake 'toxic' and said he's 'WEAK' on borders and crime

Coming into Tuesday's rally, the president had all but endorsed Flake's primary challenger Kelli Ward, and an intra-party war has broken out over what promises to be a bruising primary race

Flake's recent anti-Trump manifesto 'Conscience of a Conservative' rankled the president. In the first half-dozen pages he calls Trump's famed Twitter feed 'all noise and no signal,'

'Volatile unpredictability is not a virtue,' Flake adds. 'We have quite enough volatile actors to deal with internationally as it is without becoming one of them.'

Most telling, Flake skewers his fellow lawmakers who went along with Trump's rise to power as the lesser of two evils – the greater being Hillary Clinton.

'We pretended that the emperor wasn't naked,' he writes.

'Even worse: We checked our critical faculties at the door and pretended that the emperor was making sense.'

Despite his stinging critiques, Flake has sided in Congress with many of Trump's proposals, including two votes to repeal the Obamacare law.

Still, Trump seems prepared to throw one brushback pitch after another at Flake's head, sending a message to other recalcitrant Republicans to get in line and follow his lead. The Republican establishment is firing back.

Trump greeted U.S. Marines on Tuesday in Yuma, Arizona before departing for Phoenix

Then-candidate Trump was joined by Joe Arpaio, then the sheriff of metro Phoenix, at an Iowa campaign event in January 2016. Despite Trump coming back to Arizona at a crucial moment in his presidency, Arpaio will not be the beneficiary of his first presidential pardon on Tuesday

On Tuesday the Senate Leadership Fund, a super PAC run by a former chief of staff to Senate Majority Leader Mitch McConnell, released a vicious digital ad targeting Ward as a lunatic with 'crazy ideas' who engages in 'embarrassing behavior.'

In a sign of battle lines being drawn, Trump donor Robert Mercer – the billionaire whose money funds the Breitbart News website – donated $300,000 to a pro-Ward super PAC.

Arizona's Republican governor Doug Ducey found a way to avoid alienating either side of the spat on Tuesday, saying he would greeting Trump at the Phoenix airport but skipping the evening rally.

At least three Arizona Republican members of the House of Representatives were on hand: Andy Biggs, Trent Franks and Paul Gosar.

Phoenix's Democratic mayor called on Trump last week to cancel or postpone Tuesday's rally.

Despite garnering precious op-ed space in The Washington Post, he found himself screaming into a stiff wind.