' and also object to Hillary Clinton, who they shouted was a 'war criminal'


Police pepper sprayed and arrested a group of Communists as they attempted to burn the US flag outside the Republican National Convention.

Officers arrested 17 people after a violent melee broke out near the gates of the Quicken Loans Arena, preventing delegates and journalists from entering the stadium.

One police officer was pushed to the ground as cops attempted to separate the Communists from their rivals, which included members of a group called 'Bikers for Trump'. It was the most turbulent protest since the four-day convention began on Monday.

The third night of the convention kicked off with speeches from Texas Senator Ted Cruz, Wisoncsin governor Scott Walker, talk radio host Laura Ingraham, astronaut Eileen Collins and Kentucky State Senator Ralph Alvarado Jr.

Cruz, who ran against Trump for the Republican nomination, slammed a government that 'treated ISIS terrorists' like refugees and appeared to back one of The Donald's most controversial promises by endorsing 'building a wall to keep America safe'.

He outraged the Republican crowd by not officially endorsing Trump, who emerged near the end of his speech to wave to the crowd.

Alvarado Jr claimed Hillary Clinton did not represent the Hispanic community while Walker told a raucous crowd that the Democratic candidate is 'unfit to be president'.

Donald Trump's son Eric and his running mate Mike Pence are also scheduled to speak.

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Desecration: The black-clad group of Communists set fire to the Stars and Stripes close to the entrance to the RNC but the fire was put out

Angry scenes: Pepper spray was deployed by police as a group of Communists tried to burn Old Glory while another officer used a fire extinguisher to end the blaze

Insult: The revolutionary group, believed to be from Chicago, had advertised their intention to set fire to the Flag

Bilingual burning: The Communist agitators wore t-shirts demanding revolution in both English and Spanish as they tried to desecrate Old Glory

Ted Cruz (left), who ran against Trump for the Republican nomination, slammed a government that 'treated ISIS terrorists' while Scott Walker (right) claimed Hillary Clinton is 'unfit to be president'

Talk radio host Laura Ingraham (left) and astronaut Eileen Collins (right) were among those to speak at the convention tonight

Donald Trump's son Eric (left) and his official running mate Mike Pence are scheduled to speak on the third night of the convention

Cruz outraged the Republican crowd by not officially endorsing Trump (pictured), who emerged near the end of his speech

Two officers were attacked and suffered minor injuries in the the most turbulent protest since the four-day convention kicked off on Monday. Those arrested face charges including inciting violence and felonious assault of a police officer.

Police Chief Calvin Williams said the violence erupted when a protester whose pants caught fire became angry at a police officer who tried to put it out.

The melee brought the number of people arrested at the convention to 22. The Communists, believed to be from Chicago, had publicized their attempt to burn Old Glory and had drawn a large media crowd and onlookers.

But when the flag was produced the crowd surged forward with police - including officers from Cleveland, Ohio state troopers and Indiana state troopers - caught in the middle.

Members of the group formed a human circle with locked arms and a member in the center yelled on a megaphone: 'We're here to stand together with the people of the world, we're taking the stand against this imperialist, Republican National Convention.

'Donald Trump is an open fascist, Hillary Clinton is a proven war criminal,' the leader said.

The trouble was over within a few minutes and calm restored. Firefighters had stood by with extinguishers, but the flag was not burned successfully.

Two officers were assaulted and suffered minor injuries, Cleveland police said. The Communists had been advised not to burn their flag by officers and had left the scene.

Rounded up: Ringleaders from the group which demands an end to democracy where handcuffed by Cleveland police and Indiana state troopers, called in to bolster security

Police said it is not an offense to burn the flag, but starting a fire in a public place and endangering others was against the law (pictured, police making an arrest in Ohio)

Arrests: A Cleveland officer tries to keep order as his colleagues wrestle several of the troublemakers to the ground

Julie Leroy (pictured) was one of 17 people arrested after a violent melee broke out near the gates of the Quicken Loans Arena

Those arrested face charges including inciting violence and felonious assault of a police officer

One police officer was pushed to the ground as cops attempted to separate the Communists from their rivals

Held: Police moved in on the group quickly as the 20-strong gang tried to burn the flag

Loud: One of the protesters had used a bullhorn to call Donald Trump a 'fascist' and Hillary Clinton a 'war criminal' before being detained

Smokescreen: The combination of the attempt to burn the flag and the move by police to extinguish the blaze created smoke across the area outside the Quicken Loans Arena

Seized: The man who was holding the flag, who had a white ponytail, was grabbed by an officer then forced to the ground

Police move in: Officers carry out arrests as tensions mount outside the Quicken Loans Arena, where Republicans are holding their convention

Authorities: Police and other security officials arrest a Communist after a U.S. flag was set alight outside the gates of the Quicken Loans Arena

State troopers armed with AR-15 assault rifles stepped up security outside the Quicken Loans Arena after the most violent protests since the RNC began

A police officer carries a confiscated flag after arrests are made near the entrance to the RNC

But one witness said:' About 25 returned and the flag was brought out, the pushing and shoving began. 'It wasn't a riot and over in a minute but the cops dragged at least 10 people away.'

Police said it is not an offense to burn the flag, but starting a fire in a public place and endangering others was against the law.

The ugly scenes came as security was stepped up around the Quicken Loans Arena, which is hosting the convention.

In total more than 5,000 law enforcement agents are deployed in Cleveland for security and public order.

They include uniformed Secret Service officers, FBI agents and other federal agents with the Secret Service bringing bomb detection dogs.

Cleveland police have called in back-up from across the state, with Akron, Columbus and Cincinnati police joining them on patrol, and Ohio state troopers.

Out of state law enforcement include state troopers from Indiana, and even members of the California Highway Patrol.

The Cleveland force declines to use the term riot gear but has equipped its officers with protective equipment including helmets and body armor and issued pepper spray and has tear gas in reserve.

It has largely avoided putting officers in full protective gear on patrol until Wednesday afternoon when state troopers were seen wearing it as they patrolled around the Quicken Loans Arena.

Call for the cavalry: Mounted officers moved in to clear a path through protesters so arrested Communists could be taken to waiting vans

Show of force: Mounted officers from Cleveland and Columbus, Ohio, forces were deployed near the flag burning

Arrested: A protester is taken into custody as tensions rise in Cleveland, where Communists tried to burn the flag

Busted: A state trooper cuffs a protester as police move in on the demonstrators trying to burn the flag

Feeling blue: Cops move the busted woman out of the protest area as they take her into full custody

Locked arms: The group dedicated to overthrowing democracy started by locking arms before moving to burn Old Glory

Officers used bicycles to wall-off intersections and for the first time during the convention on Wednesday and ordered demonstrators to disperse under the threat of arrest.

Cleveland Police Chief Calvin Williams said he spent three hours on Tuesday evening riding with bicycle officers on patrol and that he waded into one confrontation because he's 'still a police officer'.

Williams said he plans to show up wherever there are 'issues' during the convention.

The police chief said the city bought 300 bicycles for the political event on the advice of police in Charlotte, North Carolina, which hosted the 2012 Democratic convention.

Officers on loan from more than a dozen police departments are on bike patrol in the city, he said.

Tensions between police and the public have been running high over the past two weeks. Two black men were shot to death by police in Louisiana and Minnesota, and eight officers were killed in two ambushes in Dallas and Baton Rouge, Louisiana.

The bike patrols have been a common sight around Cleveland in the past few days. The officers wear black helmets and shorts. Some have armored vests over their uniforms, while others have protective gear on underneath their shirts.

On Wednesday, police in riot helmets and officers on horseback joined the mix. They were used to force a path to a van for people being detained.

High-security: Members of the California Highway Patrol have been deployed on the streets with some carrying assault rifles over fears of a repeat of the Texas and Baton Rouge police murders

On guard: California Highway Patrol officers in Public Square, Cleveland. They are carrying gas masks on their right legs in case of tear gas being used

Effort: Law enforcement from Cleveland police and an Ohio state trooper were among those taking action as the flag burning was attempted

Cops move in: Ohio state troopers were among those who geared up to deal with clashes between protesters in Cleveland on Wednesday

Back-up: State troopers in riot gear were deployed as tensions escalated. Police fear that protesters are stepping up their attempts to disrupt the RNC

In the so-called event zone at the Republican convention, a 1.7-square-mile area, authorities have banned items such as tennis balls, steel-pointed umbrellas and wood posts, but firearms are permitted under state law.

In a smaller 'hard zone' surrounding the convention hall, which is temporarily under federal jurisdiction, guns are banned, meaning delegates cannot be armed on the convention floor.

The head of Cleveland's police union, however, on Sunday urged Ohio Governor John Kasich to suspend laws allowing the open display of firearms during the convention.

Kasich, who had challenged Trump for the Republican nomination, said he lacked the legal authority to take such a step.

The scale of security deployed in Cleveland is bigger than any convention since 1968. On Friday, Cleveland set up concrete traffic dividers and tall metal fences around next week's convention site, measures meant to thwart an attacker like one in Nice, France, who drove a truck into a crowd last week.

Much of the focus has been on stopping a car or truck bomb like those that struck New York's World Trade Center in 1993 and an Oklahoma City federal office building in 1995.

Cleveland has banned drones, limited the size of bags people can carry and on Friday removed opaque rubbish bins near the Quicken Loans Arena convention site, replacing them with wire frames holding clear plastic waste bags that make it more difficult to hide objects.

Ahead of the convention, authorities cleared out 1,000 spots in local jails and overflow centers in preparation for mass arrests. Courts have been opened for 20 hours a day to process arrests, according to NBC News.

Freedom of speech: Immigrant rights activists protest against Donald Trump in the course of peaceful demonstrations before the flag-burning

Focus: Donald Trump's plan to build a wall on the Mexican border was the main focus of protest on Wednesday

Sit-down protest: The protesters hit downtown Cleveland in the afternoon, shortly after Donald Trump had arrived in the city

Anti-Trump: One group of peaceful protesters highlighted their opposition to Donald Trump's policies on immigration during demonstrations in Cleveland on Wednesday

Some protesters adopted colorful outfits, with one dressed as a butterfly holding a heart-shaped sign that read: 'Let democracy fly'

Guarded: An Indiana state trooper was on guard as pro-immigration demonstrators took their anti-Trump message to the street

Authorities purchased 10,000 extra sets of plastic handcuffs, 2,500 interlocking steel security fences and 2,000 sets of riot gear with a $50million security grant.

The US Northern Command - a sector of the military that conducts homeland defense and supports civil authorities to protect the United States, Puerto Rico, Canada and Mexico - and the US Coast Guard will also be nearby.

Specialized teams of the Ohio National Guard will be waiting close by in case suspicions arise of radioactive and biological weapons in the area, the Department of Defense told CNNMoney.