
Police hurled flash grenades and used tear gas on protesters on Saturday night as anti-Trump demonstrations continued across the country in the fourth night of unrest since his shock election victory.

Seventy-one people were arrested in Portland, Oregon, where crowds threw burning road flares at officers.

Hundreds gathered outside City Hall in Los Angeles to face off against riot police after a daytime march with drew 8,000 people.

Other rallies took place in Atlanta, Salt Lake City, Washington DC, and Phoenix, as the anti-Trump backlash continued to grow.

In Indianapolis, crowds chanted 'kill the police' as they threw rocks at officers in a separate protest.

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Crowds fought through tear gas in Portland, Oregon, on Saturday night as they clashed with police in the fourth night of protests since Donald Trump's election victory

Heavily armed police in riot gear were forced to use flash grenades on the crowds after coming under fire from rioters throwing rocks, bottles and burning road flares at them

Thousands of people marched through Los Angeles in a peaceful protest on Saturday during the daytime. It descended into a more sinister scene later, with armed police patrolling the streets

Protesters also marched through the Las Vegas strip as the nationwide unrest continued to grow

Police also used pepper spray to fight off crowds as others wrestled with officers who officially declared riots earlier in the week

Protesters run from plumes of tear gas in Portland, Oregon, on the fourth night of chaos since Trump's election

Crowds run from tear gas in Portland, Oregon, where protesters showed no signs of relenting their efforts

Police in Portland revealed they had used flash grenades on crowds after being attacked by burning road flares

In Portland, officers battled crowds for the fourth night in a row and were forced to resort to using flash grenades to control them.

The department revealed on Sunday that 71 people had been arrested throughout the night. They were transported to precincts on an arranged bus.

A police vehicle was also spray painted with an anti-Trump message. Among those arrested was an 18-year-old who was charged with possession of a concealed weapon.

The Oregon city has played host to some of the worst of the riots since Trump's shock election win. A man was shot overnight on Friday as crowds marched around him.

Police are still sharing CCTV images of vandals smashing store fronts and car windows to try to identify those responsible for the chaos.

Indianapolis saw pro and anti-Trump voters clash, with one bold Republican driving a military truck through crowds wielding a 'Trump Pence 2016' sign.

There were also protests in Chicago, where thousands marched through the streets of downtown and rallied outside Trump's hotel in the city.

In Los Angeles, police said 8,000 people had gathered to march peacefully during the day.

Protesters spray-painted police patrol cars in Los Angeles with anti-Trump graffiti as the protests raged through Saturday night

In Los Angeles, protesters complained about the electoral college process which does not take into account the popular vote

Riot police in Los Angeles controlled crowds outside City Hall where scores had gathered with signs after an earlier march saw 8,000 take to the streets

The heavily armed police were called to control the crowd of around 300 people who had gathered at the scene

In New York, marches continued into Sunday afternoon where hundreds took to Washington Square Park

Others flocked to Trump Tower on Fifth Avenue for another day of protesting outside the President-elect's Manhattan home

Children were among those at the demonstration in New York on Sunday where protesters labeled Trump 'racist, sexist and anti-gay'

Later, a smaller crowd of around 300 gathered outside City Hall to carry on the protest but were dispersed by heavily armed officers.

No one was arrested at either event and police commended the crowds for their 'unity'.

'LAPD continues to work tirelessly to protect the 1st Amendment Right of the people today and always. Be safe and peaceful!' read a tweet posted early on Saturday.

Later, officers continued: 'Approximately 8,000 protesters in DTLA today exervising their 1st Amendment Right. No arrests have been made. United we stand divided we fall.

'Approx 1100 protesters in the DTLA area continue to express their freedom of speech and assembly peacefully. Thank you for the unity.'

The presence of heavily armed squads made for a sinister atmosphere in the city.

In Washington, two animated demonstrates high five as cars pass through crowds of chanting Clinton voters

Protesters wore masks favored by hacking group Anonymous in Miami where the same 'dump Trump' and 'not my president' signs were carried

A large crowd of protesters is seen gathered in Indianapolis on Saturday night during demonstrations against President-elect Donald Trump

A young woman is seen in Indianapolis holding a sign that reads, 'Not My President', as she is surrounded by other protesters

More protesters in Washington march to tell Trump they are his 'worst nightmare' in the fourth night of chaos since his shock election win

A woman is arrested by an Indianapolis Police Officer and walked in front of mounted officers during a rally against Donald Trump on Saturday

Aiyana Stanley-Jones leads a rally against the election of Republican Donald Trump as President of the United States in Indianapolis

A Donald Trump fan was seen driving towards protesters in Indianapolis in a military-style truck with a 'Trump Pence 2016' sign on the side of the vehicle

David Jackson (C), who voted for Donald Trump, has a discussion with two protesters who oppose Donald Trump in downtown Indianapolis on Saturday night

A woman who did not want to be identified is dragged back from the street during a rally against Donald Trump in Indianapolis

A man is seen carrying a sign that reads, 'no human being is illegal #notmypresident', among many other protesters in downtown Indianapolis

Protesters hold signs during an election protest in Lafayette Square Park in front of the White House, Saturday, Nov. 12

Washington DC was another city where protesters marched against President-elect Donald Trump on Saturday night. Pictured are two women holding anti-Trump signs

Crowds of people are seen on both sides of the street outside a hotel in downtown Indianapolis during anti-Trump protests on Saturday night

Protesters against President-elect Donald Trump chant in front of Trump International Hotel in Las Vegas on November 12, 2016

In Las Vegas, hundreds marched through the strip carrying signs with similar messages as the protests continued

Massive crowds of protesters took tot he streets in Las Vegas - joining a host of other cities across the country to stage demonstrations

The massive crowd of anti-Trump protesters marched along the Strip on Saturday night, many carrying signs and banners

Demonstrators gathered in Salt Lake City, Utah, on Saturday to protest against Donald Trump's election victory over Hillary Clinton

A crowd of protesters staged a rally outside the Utah State Capitol building in Salt Lake City on Saturday

Demonstrators gather in protest against the election of Republican Donald Trump as President of the United States in Salt Lake City, Utah

A man at the protests in Salt Lake City wears a hat that reads, 'Immigrants Make America Great'. It mocked Donald Trump's campaign slogan

A man is arrested outside the Indiana State House in Indianapolis during a rally against the election of Donald Trump on Saturday night

Jocelyn Dominguez, 9, sits on the shoulders of her father Moises during a rally against the election of Republican Donald Trump in Indianapolis on Saturday night

After getting her Trump sign knocked out of her hand, Kelly Cummins (L) yells at a protester marching against the Republican's election win

Protesters are seen in Miami, Florida, upset with Republican nominee Donald Trump's election win on Tuesday over Hillary Clinton

Protestors attend a rally in Wynwood, Miami to protest against President-elect Donald Trump

Meanwhile in New York, Liberal film-maker Michael Moore made it to the fourth floor of Manhattan's Trump Tower in his bid to confront President-elect Trump and call on him to step down, before he was stopped by Secret Service guards.

Moore, who had been a vocal critic of Trump during the election, joined thousands of people in protesters in Manhattan on Saturday morning, before he managed to get inside Trump Tower.

After making his way into the Donald's Central Park skyscraper, Moore attempted to get to Trump's office.

Kansas City, Missouri, was another city that saw more protests against Donald Trump on Saturday. An anti-Trump crowd is seen in the city

A demonstrator who painted her face in the colors of the American flag holds up a sign heading, 'Stop Trump', in Kansas City on Saturday

People attend a protest against the election of President-elect Donald Trump Saturday, Nov. 12, 2016, in Kansas City outside of City Hall

People protest against the election of Republican candidate Donald Trump in Kansas City, Missouri, on Saturday afternoon

A large crowd of demonstrators hold anti-Donald Trump signs during a Missouri rally against the President-elect

Donald Trump supporter Kern Carlos Huerta stands in front of the Utah State Capitol building doors as demonstrators protest against the election of Republican nominee

Film-maker Michael Moore has called on Donald Trump to step down as President-elect before he even takes office, after joining in protests in New York City

The award-winning film-maker managed to scale Trump's famous escalator, however he was stopped from going any further by security guards on the fourth floor.

Moore was then escorted back down to the lobby, however before he left he wrote a note to Trump.

'Mr. Trump. I’m here. I want to talk to you,' the note read.

Moore then left the building and tweeted: 'I'm in the middle of thousands -tens of thousands?- of American voters outside Trump Tower demanding he step aside. He got the least votes.

Michael Moore holds up his phone to broadcast his appearance at an anti-Donald Trump rally in New York on Saturday

Moore scaled the famous escalator inside Trump Tower in an attempt to reach the President-elect's office, but he was stopped by security

Moore's face is seen on the screen of his phone, while standing among a crowd of thousands of protesters in New York

'I was able to get into Trump Tower & deliver him a message: "You lost. Step aside." SS took the note I wrote up & went 2 give it to him.'

Moore broadcast his journey into Trump Tower on Facebook Live.

After leaving the building, he spoke with protesters outside for more than an hour.

British right-wing politician Nigel Farage arrived at Trump Tower shortly after Moore left. He was allowed up to Trump's office.

Filmmaker Michael Moore walks inside Trump Tower in New York on Saturday, Nov. 12, 2016

Moore is seen leaving a note for Trump before he left the Tower. The note reads: 'Mr Trump. I’m here. I want to talk to you'

After being escorted out of the building, Moore tweeted about the note he wrote Trump

Michael Moore talks to a film crew as he is blocked exits to an elevator inside Trump Tower by Secret Service officers

Demonstrators hold signs during a rally outside Trump Tower in New York on Saturday, Nov. 12

Thousands of protesters march up Fifth Avenue to Trump Tower to protest against President-elect Donald Trump, in Manhattan

About 2,000 protesters have been marching along Fifth Avenue in Manhattan shouting "not my president" and other slogans.

The protesters rallied at New York's Union Square on Saturday before picking up steam and taking their cause into the street and toward Trump Tower.

Fifth Avenue was crowded with protesters for blocks. Police lined both sides, following along on foot and on motorcycle, but the group remained peaceful.

There were protests in other parts of the country as well, with the largest taking place in Los Angeles, where several thousands marched.

New York police officers block demonstrators during rallies outside Trump Tower in Manhattan on Saturday night

Protesters are seen in the streets of New York during an anti-Trump demonstration on Saturday night

Ellen Marius, right, and Majo Orozco chant slogans as they demonstrate during a rally outside Trump Tower in New York on Saturday, Nov. 12

There were also protests against Trump in Los Angeles on Saturday, with thousands seen marching through the streets downtown

Anti-Trump demonstrators hold a U.S. flag upside-down as they march in a rally in downtown Los Angeles on Saturday, Nov. 12, 2016, to protest against President-elect Donald Trump

Protesters were denouncing his campaign pledge to deport people who entered the US illegally and his crude comments about women.

Cheers, chants and flag-waving mark Saturday's procession, which stretched for blocks through the Civic Center.

No arrests were made even though the train of demonstrators occasionally snarled traffic.

The mood seemed enthusiastic rather than angry. There are no reports of vandalism or fire-setting, which have marred previous demonstrations around the nation.

Earlier in the day, Trump's campaign manager, Kellyanne Conway was seen at Trump Tower in New York.

She spoke briefly with reporters before taking an elevator to the President-elect's office.

A protester is seen walking along the street in New York carrying a sign during an anti-Donald Trump rally on Saturday

Protesters carry American flags, one of which was modified to include the 'Peace' Symbol, during demonstrations against Donald Trump in New York

Chong Cha demonstrates with her dog, Zuzu, during a rally outside Trump Tower in New York on Saturday, Nov. 12, 2016

Kellyanne Conway was seen earlier in the day arriving at Trump Tower for meetings with the President-elect

British far-right politician Nigel Farage visited Trump Tower on Sunday shortly after Moore left. Farage was allowed up to meet with Trump

Moore came under fire last month for calling Trump supporters 'legal terrorists' in an interview with Rolling Stone.

In the interview, he said Trump would 'blow up the system' and his voters would 'participate in the detonation'.

Moore also compared Trump to a pedophile, saying voters had to protect America from the GOP nominee the way children should be protected from molesters.