WASHINGTON/MINNEAPOLIS • US protesters ignored curfews as they vented their anger over the death of an unarmed black man at the hands of police, but there was a marked drop in the violence that had prompted President Donald Trump to threaten to deploy the military.

Mr George Floyd died after a white policeman pinned his knee on his neck for nearly nine minutes in Minneapolis on May 25, reigniting the explosive issue of police brutality against African Americans five months before the November presidential election.

Tens of thousands of people took to the streets of cities from coast to coast for an eighth night as National Guard troops lined the steps of the Lincoln Memorial in Washington.

There was sporadic violence in Washington and Portland, Oregon, with protesters tossing fireworks and bottles answered by police flash grenades and tear gas.

Clashes between protesters and police and the looting of some stores in New York gave way to relative quiet in the early hours of yesterday. Police told media they made 200 arrests, largely for curfew violations.

In Los Angeles, many demonstrators who defied the curfew were arrested, but by mid-evening, calm had been restored to the extent that television stations switched from wall-to-wall coverage back to regular programming.

Large marches and rallies also took place in Philadelphia, Atlanta, Denver and Seattle.

The officer who knelt on Mr Floyd, Derek Chauvin, 44, has been charged with third-degree murder and second-degree manslaughter.

Three other officers involved were fired but have not been charged.

Although rallies on behalf of Mr Floyd and other victims of police brutality in recent days have been largely peaceful, after dark, many turned to vandalism, arson and looting. On Monday night, five police officers were hit by gunfire in two cities.

Outside the US Capitol Building on Tuesday afternoon, a throng took a knee, chanting "silence is violence" and "no justice, no peace", as officers faced them just before the government-imposed curfew.

Many of the protesters used the slogan "take a knee", referring both to how Mr Floyd died and a longstanding protest against racism in the US that started in 2016 with a football player taking a knee instead of standing during the national anthem.

The crowd remained after dark, despite the curfew and vows by Mr Trump to crack down on what he has called lawlessness by "hoodlums" and "thugs", using National Guard troops or even the US military if necessary.

In Atlanta, four officers and two former officers were charged with using excessive force while arresting two students.

Minneapolis launched an investigation into possible discriminatory practices in the police department over the past 10 years.

In New York, thousands of chanting protesters ignored the curfew to march from the Barclays Centre in Flatbush towards the Brooklyn Bridge as police helicopters whirred overhead.

The crowd halted at an entrance to the Manhattan Bridge roadway and chanted at riot police: "Walk with us, walk with us."

Protests have spread overseas. In central London, thousands of people gathered yesterday, chanting "no justice, no peace" and "black lives matter", Reuters reporters said. Many of the protesters wore red and face masks. Some waved banners with slogans such as: "The UK is not innocent: Less racist is still racist" and "Racism is a global issue". Others chanted "George Floyd" and "black lives matter".

In Rome, Pope Francis called for national reconciliation in the United States, saying that while racism is intolerable, the street violence that has broken out is "self-destructive and self-defeating".

Back in Minneapolis, Ms Roxie Washington, mother of Mr Floyd's six-year-old daughter Gianna, told a news conference that he was a good man.

"I want everybody to know that this is what those officers took from me," she said, sobbing. "Gianna does not have a father. He will never see her grow up, graduate."

REUTERS