Dozens arrested, few injured as 40,000 protesters descend on Boston The free speech rally ended early today at Boston Common.

 -- One week after violent protests rattled Charlottesville, Virginia, a scheduled free speech rally in Boston Saturday was met with thousands of counterprotesters, but the day went off mostly smoothly, police said, with 33 arrests but few injuries.

The free speech rally was deemed "officially over" by police ahead of its official end time, but thousands of counterprotesters continued to spread out in the city throughout the afternoon, with some protesting peacefully but others confronting officers and people.

A total of 33 arrests were made Saturday, mostly from disorderly conduct and a few assaults on police officers, the Boston Police Department announced. Police Commissioner William Evans said at a news conference this afternoon that some urine-filled bottles were thrown at officers, and police indicated on Twitter that some demonstrators were throwing rocks at police.

But for the most part, Evans said, the day of direct action went off smoothly as police planned, with very little injury and property damage.

"Overall I thought we got the First Amendment people in, we got them out, no one got hurt, no one got killed," he said.

Police did stop three people with ballistic vests and a gun, Evans said, "but we were lucky to get those three out of here and confiscate the vests."

Evans said roughly 40,000 people descended on Boston Saturday, "standing tall against hatred and bigotry in our city, and that's a good feeling." He added that he wished the "trouble makers stayed away," who he said weren't there for either the free speech side or the counterprotesters' side, but "were here just to cause problems."

Evans said that "99.9 percent of the people here were for the right reasons -- that's to fight bigotry and hate."

Saturday's massive gathering of demonstrators across Boston was sparked by a free speech rally set to take place from noon to 2 p.m. at Boston Common. But the rally was deemed "officially over" in a tweet from Boston police at 1:30 p.m ET, and police said the demonstrators had left the Common.

Libertarian congressional candidate Samson Racioppi, who was set to speak at the free speech event, told ABC affiliate WCVB, "I really think it was supposed to be a good event by the organizers, but it kind of fell apart."

An organizer of the free speech event said the group has no affiliation with the white supremacists involved in the violence in Charlottesville, but a small number of Ku Klux Klan members were expected to attend, ABC affiliate WCVB in Boston reported.

After the free speech event has concluded, counterprotesters still swarmed Boston this afternoon, and riot police also responded in the city.

The giant crowds of counterprotesters first gathered in the city this morning holding signs with phrases like, "hate speech is not free speech" and "white silence is violence."

Counterprotesters chanted "no fascists, no KKK, no racist USA."

One Massachusetts woman who drove three hours to Boston to attend today's counterprotest told ABC News she has felt "months of depression" and "absolute outrage."

"And after Saturday [at Charlottesville]," she said, "I just cannot be silent anymore."

Of the free speech rally attendees, she said, "I was glad to see that their crowd was very small. That spoke volumes to me.

"We have a really long way to go and we have to end white supremacy in all of its forms," she added.

Another counterprotester told ABC News, "I just wanted to come out and confront them head on, and I didn't want to miss this chance."

"I didn't think that we would ever have to have this confrontation in 2017," she said, "so it feels really vital to just come out and try to stamp it out today. And I'm encouraged by how many other people came out."

While many counterprotesters marched peacefully, some scuffled with armed officers.

Video showed several officers taking an individual to the ground after he angrily confronted the officers.

Amid the confrontations, Boston police tweeted that individuals are asked to "refrain from throwing urine, bottles and other harmful projectiles at our officers."

President Trump on Saturday afternoon thanked the police in a tweet, saying they look "tough and smart" against what he said appeared to be "anti-police agitators."

Great job by all law enforcement officers and Boston Mayor @Marty_Walsh. — Donald J. Trump (@realDonaldTrump) August 19, 2017

Trump also tweeted, "I want to applaud the many protestors in Boston who are speaking out against bigotry and hate. Our country will soon come together as one!" Boston Mayor Marty Wash responded to that message by saying that his city stood together for "peace and love."

First daughter Ivanka Trump on Saturday night tweeted, "It was beautiful to see thousands of people across the U.S.A come together today to peacefully denounce bigotry, racism & anti-Semitism ... We must continue to come together, united as Americans!"

Throughout the day, protesters also scuffled with each other.

In one tense scene between a man and a counterprotester at the Common, the counterprotester followed the man, saying, "We only hate hate." The man shouted, "Get away from me. Stay right there! You're not even a me [sic], you're not even a woman, you're an it!" As the man walked away, he kicked and punched into the air, leading one counterprotester to yell "Get your bigotry out of here, a------." The man shoved another counterprotester, which caused more people to step in to make sure the situation didn't escalate.

Boston city officials said they planned to deploy hundreds of police officers today to prevent violence similar to what took place in Charlottesville last weekend, where a rally by white nationalists, including neo-Nazis, skinheads and Ku Klux Klan members demonstrating over plans to remove a Robert E. Lee statue, ended in the death of a counterprotester after a car was rammed into a crowd that was marching through the streets.

"We're going to respect their right to free speech,” Walsh said Friday, but "they don't have the right to create unsafe conditions."

Scheduled to speak at the free speech rally, which was organized by the Boston Free Speech Coalition, were Kyle Chapman, who caused controversy online after photos emerged of him hitting anti-Trump protesters, Joe Biggs, who previously worked at the website InfoWars, run by conservative radio host Alex Jones, Republican congressional candidate Shiva Ayyadurai and Racioppi.

Walsh said that some of those invited to speak "spew hate," The Associated Press reported.

John Medlar, who said he is an organizer for Boston Free Speech, said the group has no affiliation with the white supremacists who marched in Charlottesville, Boston.com reported.

"While we maintain that every individual is entitled to their freedom of speech, and defend that basic human right, we will not be offering our platform to racism or bigotry. We denounce the politics of supremacy and violence," the group wrote on its Facebook page.

The group is largely made up of students in their mid-teens to mid-20s, Medlar told Boston.com.

WCVB reported that the KKK’s national director, Thomas Robb, said as many as five KKK members from Springfield and possibly more from Boston were planning to attend today's rally.

Several other rallies were planned across the U.S. Saturday. Many are in response to the Charlottesville violence last weekend, as well as the movement to remove Confederate statues across the country, and in reaction to Trump’s controversial press conference on Tuesday.

The "Rally Against White Supremacy" took place in Austin, Texas, while the “Black Lives Matter Protests to remove Confederate statues” took place in Houston, and the “United Against HATE: Demand Racist President Trump Resign” rally was held in Grand Rapids, Michigan.

Events were also planned in cities including Atlanta, New Orleans and Dallas.

ABC News' Erin Keohane and Meghan Keneally contributed to this report.

Great job by all law enforcement officers and Boston Mayor @Marty_Walsh.

Trump also tweeted, "I want to applaud the many protestors in Boston who are speaking out against bigotry and hate. Our country will soon come together as one!" Boston Mayor Marty Wash responded to that message by saying that his city stood together for "peace and love."

First daughter Ivanka Trump on Saturday night tweeted, "It was beautiful to see thousands of people across the U.S.A come together today to peacefully denounce bigotry, racism & anti-Semitism ... We must continue to come together, united as Americans!"

Throughout the day, protesters also scuffled with each other.

In one tense scene between a man and a counterprotester at the Common, the counterprotester followed the man, saying, "We only hate hate." The man shouted, "Get away from me. Stay right there! You're not even a me [sic], you're not even a woman, you're an it!" As the man walked away, he kicked and punched into the air, leading one counterprotester to yell "Get your bigotry out of here, a------." The man shoved another counterprotester, which caused more people to step in to make sure the situation didn't escalate.

Boston city officials said they planned to deploy hundreds of police officers today to prevent violence similar to what took place in Charlottesville last weekend, where a rally by white nationalists, including neo-Nazis, skinheads and Ku Klux Klan members demonstrating over plans to remove a Robert E. Lee statue, ended in the death of a counterprotester after a car was rammed into a crowd that was marching through the streets.

"We're going to respect their right to free speech,” Walsh said Friday, but "they don't have the right to create unsafe conditions."

Scheduled to speak at the free speech rally, which was organized by the Boston Free Speech Coalition, were Kyle Chapman, who caused controversy online after photos emerged of him hitting anti-Trump protesters, Joe Biggs, who previously worked at the website InfoWars, run by conservative radio host Alex Jones, Republican congressional candidate Shiva Ayyadurai and Racioppi.

Walsh said that some of those invited to speak "spew hate," The Associated Press reported.

John Medlar, who said he is an organizer for Boston Free Speech, said the group has no affiliation with the white supremacists who marched in Charlottesville, Boston.com reported.

"While we maintain that every individual is entitled to their freedom of speech, and defend that basic human right, we will not be offering our platform to racism or bigotry. We denounce the politics of supremacy and violence," the group wrote on its Facebook page.

The group is largely made up of students in their mid-teens to mid-20s, Medlar told Boston.com.

WCVB reported that the KKK’s national director, Thomas Robb, said as many as five KKK members from Springfield and possibly more from Boston were planning to attend today's rally.

Several other rallies were planned across the U.S. Saturday. Many are in response to the Charlottesville violence last weekend, as well as the movement to remove Confederate statues across the country, and in reaction to Trump’s controversial press conference on Tuesday.

The "Rally Against White Supremacy" took place in Austin, Texas, while the “Black Lives Matter Protests to remove Confederate statues” took place in Houston, and the “United Against HATE: Demand Racist President Trump Resign” rally was held in Grand Rapids, Michigan.

Events were also planned in cities including Atlanta, New Orleans and Dallas.

ABC News' Erin Keohane and Meghan Keneally contributed to this report.