Violence erupted for a seventh night across several parts of the US, just hours after President Donald Trump vowed to use military personnel to halt the protests.
"Mayors and governors must establish an overwhelming law enforcement presence until the violence has been quelled," Trump said.
"If a city or state refuses to take the actions that are necessary to defend the life and property of their residents, then I will deploy the United States military and quickly solve the problem for them."
Following his address, he walked from the White House to nearby St. John's Episcopal Church amid tight security to pose for pictures with his daughter Ivanka.
However, a few hours later, thousands of people marched through the streets of Brooklyn, shouting "justice now!", while demonstrators in Los Angeles and New York City clashed with riot police.
George Floyd, a 46-year-old African-American, was killed minutes after a policeman pinned his neck under a knee for nearly nine minutes.
U.S. President Donald Trump fired General Timothy Haugh as director of the National Security Agency on Thursday, according to two officials familiar with the decision, and congressional Democrats denounced the removal of the nonpartisan official from a top security post.
Israel stepped up airstrikes on Syria, declaring the attacks a warning to the new rulers in Damascus as it accused their ally Turkey of trying to turn the country into a Turkish protectorate.
The Trump administration moved forward with the sale of more than 20,000 US-made assault rifles to Israel last month, according to a document seen by Reuters, pushing ahead with a sale that the administration of former president Joe Biden had delayed.