LOUISVILLE (Kentucky) • Armed police supporters and anti-racism demonstrators clashed in Louisville before the Kentucky Derby horse race, while Rochester police used tear gas to disperse protesters, as discord in cities across the US continues to simmer.

Protesters in Portland, Oregon, threw fire bombs at police last Saturday night and at least one person was injured, police said, on the 100th day of demonstrations in the West Coast city over racial injustice and police brutality.

In the afternoon, hundreds of protesters marched towards the Churchill Downs track in Louisville chanting, "No Justice, No Derby" - a nod to activists' calls to cancel the annual race, which was being held without spectators because of the coronavirus.

Separately, roughly 250 members of a black militia group named NFAC that has protested against the police killings of black people assembled outside Churchill Downs, all armed with long guns.

NFAC leader John "Grandmaster Jay" Johnson taunted the officers standing guard in front of the race track, but the group later retreated without incident.

Louisville has emerged as a key flashpoint in a summer of unrest because of outrage over the death of Ms Breonna Taylor, a 26-year-old black woman who was killed in March when the city's police burst into her apartment using a so-called "no-knock" arrest warrant that did not require them to announce themselves.

Ms Sadiqa Reynolds, president of the Louisville Urban League, said that while the race was not cancelled as hoped, she believes the protesters' demands - which include holding officers involved in Ms Taylor's death accountable - were heard.

"Today was a show of force from the community of Louisville to say that enough is enough," she told Reuters. "We are tired of our lives not mattering."

Earlier on Saturday, a group of counter-protesters, brandishing pistols and long guns squared off against Black Lives Matter protesters and got into shoving matches in a park downtown.

People on both sides screamed at each other, faces centimetres apart. After about 45 minutes, police cleared the people from the park, but the protests outside Churchill Downs continued.

The counter-protesters included about 250 pro-police demonstrators, including Mr Dylan Stevens, who goes by the nickname "The Angry Viking" and claims to lead a group of what he calls "Patriots".

According to his website, Mr Stevens supports Republican President Donald Trump, the police, the military and the right to bear arms.

Mr Stevens, who was armed and dressed in tactical gear, told protesters he was not there to oppose them, according to the Louisville Courier-Journal.

He said his group had come because of a threat made by NFAC leader Johnson in July to "burn the city to the ground" if justice was not done in the Taylor case, the Courier-Journal reported.

Demonstrations against racism and police brutality have swept the US since May 25, when Mr George Floyd, a black man, died after a Minneapolis police officer knelt on his neck for nearly nine minutes.

Over in Rochester, New York, police used batons, pepper balls and tear gas to push back about 2,000 protesters who marched towards the Public Safety Building last Saturday night, chanting "Black Lives Matter" and "Daniel Prude" - a reference to a black man who died after an encounter with the police in March.

The Rochester Police Department said in a statement that protesters had ignored their orders to disperse, and that some hurled bottles, rocks and fireworks at officers.

Demonstrators started their march at the site of Mr Prude's arrest. It was the fourth night of protests, which came after Mr Prude's family released body camera footage showing officers pinned Mr Prude to the pavement and restrained him with a hood.

In Portland, police described what they called "tumultuous and violent conduct" by protesters on the city's Stark Street.

"Fire bombs were thrown at officers, injuring at least one community member," police said on Twitter, while re-tweeting a video posted by a New York Times reporter showing fire bombs being thrown and a protester running with his legs on fire.

Portland has seen nightly protests for over three months that have at times turned into violent clashes between demonstrators and officers, as well as between right-and left-wing groups. Police said they made arrests but did not give a number.

REUTERS