Violent protests over the death of an unarmed African-American man at the hands of police officers in Minnesota “are no longer in any way” about his killing, the state’s governor has said.
Tim Walz spoke after a night of unrest in several US cities over the death of George Floyd in Minneapolis.
He said that as a result he was taking the unprecedented step of mobilising the state’s entire National Guard.
There are also reports that military police units could deploy.
An ex-Minneapolis policeman has been charged with murder over the death of Mr Floyd, 46, in police custody on Monday.
Derek Chauvin, who is white, was shown in footage kneeling on Mr Floyd’s neck for several minutes, even after he said he couldn’t breathe. He and three other officers have since been sacked.
The video went viral online, reigniting US anger over police killings of black Americans, and reopening deep wounds over racial inequality across the nation.
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On Friday night protesters clashed with police in cities including New York, Atlanta and Portland. In Washington DC, the White House was briefly locked down.
In Minnesota, “our great cities of Minneapolis and St. Paul are under assault,” Mr Walz said. “The situation in Minneapolis is now about attacking civil society, instilling fear and disrupting our great city.”
He said violence on Friday night had made “a mockery of pretending this is about George Floyd’s death, or inequities or historical traumas to our communities of colour”.
He and other officials have suggested that many violent protesters came from outside the state
Mr Chauvin, 44, is due to appear in court in Minneapolis for the first time on Monday.