Thousands of people have taken to the streets in European and Asian cities, demonstrating in support of US protests against police brutality.
The rolling, global protests reflect rising anger over police treatment of ethnic minorities, sparked by the May 25 killing of George Floyd in Minneapolis.
After a largely peaceful protest in London on Saturday, a few demonstrators near British Prime Minister Boris Johnson's residence threw bottles at police, and mounted officers charged at protesters and pushed them back.
Earlier, more than a thousand protesters had marched past the US Embassy, blocking traffic and holding placards.
Many thousands had also crowded into the square outside parliament, holding placards reading "Black Lives Matter", ignoring government advice to avoid large gatherings due to the risk from the coronavirus.
"I have come down in support of black people who have been ill-treated for many, many, many, many years. It is time for a change," 39-year-old primary school teacher Aisha Pemberton said.
Police in the German city of Hamburg used pepper spray on protesters and said they were ready to deploy water cannons. One officer was injured, they added.
Several hundred "hooded and aggressive people" had put officers under pressure in the city centre, police said, tweeting: "Attacks on police officers are unacceptable!"
In Paris authorities banned demonstrations planned outside the US Embassy and on the lawns near the Eiffel Tower.
However, several hundred protesters, some holding "Black Lives Matters" signs, gathered on Place de la Concorde, close to the embassy.
Police had installed a long barrier across the square to prevent access to the embassy, which is also close to the Elysee presidential palace.
In Berlin, demonstrators filled the central Alexanderplatz square, while there was also a protest in Warsaw.
Floyd, 46, died after a white police officer detaining him knelt on his neck for nearly nine minutes with fellow officers beside him.
In Brisbane, police estimated 10,000 people joined a peaceful protest, wearing masks and holding "Black Lives Matter" placards.
Many wrapped themselves in indigenous flags, calling for an end to police mistreatment of indigenous Australians.
Banners and slogans have focused not just on George Floyd but on a string of other controversies in different countries as well as mistreatment of minorities in general.
In Sydney, a last-minute court decision overruling a ban imposed because of the coronavirus allowed several thousand people to legally march, with a heavy police presence.
In Tokyo, marchers protested against what they said was police mistreatment of a Kurdish man who says he was stopped while driving and shoved to the ground.
Organisers said they were also marching in support of the Black Lives Matter movement.
"I want to show that there's racism in Japan now," said 17-year-old high school student Wakaba, who declined to give her family name.
In Seoul, dozens of South Korean activists and foreign residents gathered, some wearing black masks with "Can't breathe" in Korean, echoing Floyd's final words as he lay on the ground.
Australian Associated Press