Beyoncé called for justice for George Floyd, saying "we all witnessed his murder in broad daylight" and that "we can no longer look away".
"There will be another protest in Appleton Sunday at 5 p.m".
Others held up placards saying "Racism has no place" and "I can't breathe" - words Mr Floyd told the police officer who was restraining him.
A police officer was seen in the footage of an amateur video pressing his knee on the neck of George Floyd, an unarmed male African American, for several minutes although the latter had been arrested, handcuffed and pinned to the ground.
Thousands gathered in central London on Sunday to offer support for American demonstrators.
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Ces données émanent de Surgisphere , qui se présente comme une société d'analyse de données de santé, basée aux Etats-Unis. L'utilisation de la molécule défendue bec et ongles par le professeur Didier Raoult semblait donc définitivement enterrée.
The demonstrations have morphed into wider anger over police killings of black men.
Protests have flared up across the United States after the death of George Floyd in Minneapolis this week. Several hundred more people took to the streets Sunday in the capital's Kreuzberg area, carrying signs with slogans like "Silence is Violence", "Hold Cops Accountable", and "Who Do You Call When Police Murder?"
Activists took to the streets in Floyd's home state Minneapolis and across the USA to protest alleged police brutality against African-American men.
He also noted the Minnesota Governor's warning that "anarchist and white supremacy groups were trying to fuel the chaos".
With the protests entering its fifth day in the USA, the marches are now spreading to other countries.
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Certains protestataires ont alors réussi à forcer les barrières de sécurité, à briser les vitres et à mettre le feu au bâtiment. Aussi faut-il ajouter que les soulèvements et les révoltes dus à cet incident continuent dans plusieurs villes américaines.
Hu Xijin, the editor of the state-owned Global Times newspaper, tweeted that US officials can now see protests out their own windows: "I want to ask Speaker Pelosi and Secretary Pompeo: Should Beijing support protests in the USA, like you glorified rioters in Hong Kong?"
Tens of thousands of people have joined nightly protests across the USA since the death, with at least 1,600 people arrested in 22 cities as some demonstrations descended into violence.
Hua Chunying, a Chinese foreign ministry spokeswoman, pointed out America's racial unrest by tweeting "I can't breathe" - a phrase spoken by Mr Floyd repeatedly before his death.
One TV anchor discussed "a terrible scene from NY, where police attacked protesters".
Russian Federation accused the United States of "systemic problems in the human rights sphere".
Trump actions on Hong Kong just threats for now
Trump has blasted Beijing for tampering with Hong Kong's autonomy and laid out his decision to do away with Hong Kong's privileges.