A police officer who fatally shot an unarmed black motorist in Tulsa, Oklahoma, has been charged with manslaughter, a prosecutor has said.
District Attorney Steve Kunzweiler has filed first-degree manslaughter charges against Officer Betty Shelby.
Ms Shelby shot and killed Terence Crutcher, 40, last week while he was standing next to his broken-down car.
In Charlotte, North Carolina, there have been two nights of violence over a fatal police shooting there.
Keith Lamont Scott, a 43-year-old black man, was shot by a black officer on Tuesday.
Police said he refused to drop his gun but his family say he was unarmed and holding a book.
A video showing the shooting will be viewed by Mr Scott’s family soon.
The police use of force against black men has for two years been the subject of protests across the US, and now it has also become an election issue.
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Four days before the first debate, Republican Donald Trump has said the violence is largely due to drugs.
“If you’re not aware, drugs are a very, very big factor in what you’re watching on television at night,” he said.
Democratic vice presidential candidate Tim Kaine said the list of black men fatally shot by police has “grown too long” and the country needed to confront the issue of racial tensions.
In the aftermath of the Tulsa shooting, Officer Shelby said Mr Crutcher did not follow her commands and she opened fire when he began to reach into his car window.
Ms Shelby’s lawyer, Scott Wood, has said she believed Mr Crutcher was under the influence of the synthetic drug, PCP. A vial of the drug was found in the car.
His family have disputed Ms Shelby’s claim, arguing that his window was closed at the time of the incident.
Police have said no gun was found on Mr Crutcher or inside his vehicle.
As well as being shot, Mr Crutcher was also struck with a stun gun by another officer.
His death sparked protests in Tulsa too, but these have been peaceful.
Mr Kunzweiler said a warrant has been issued for Ms Shelby’s arrest. She faces a minimum of four years in prison.
The US Justice Department has also opened a separate investigation to see if Mr Crutcher’s civil rights were violated.