Hundreds of demonstrators took to the streets in North Carolina after police shot and killed a black man while they were looking for a different person.
More than 200 protesters had gathered in Charlotte after a black police officer shot dead Keith Lamont Scott, just days after it was reported a white officer killed an unarmed black man in Oklahoma.
Police said in a statement that the 43-year-old got out of his car holding a firearm and posed an "imminent deadly threat".
Department spokesman Keith Trietley said that he got out of the car and back in, and when officers approached he got out of the car again with a gun, and at least one officer fired a weapon.
Scott was taken to Carolinas Medical Centre and pronounced dead.
Posts on social media reported that Scott was unarmed and disabled, and family members say he was holding a book and waiting to pick up his son from school.
Joe Bruno, a reporter from local news station WSOC tweeted this footage of Lamont Scott's sister, saying "he didn't have no gun, he wasn't messing with anybody":
Police said that a weapon had been recovered from Mr Lamont Scott, but did not comment on whether he was disabled or not.
The protest began to disperse late on Tuesday night after police fired tear gas on the crowd and an emergency unit was dispatched to remove officers.
Charlotte-Mecklenburg Police Department reported that 12 officers had been injured in the demonstration and that protesters had been destroying police vehicles.
Demonstrators at the scene, some carrying signs reading "Black Lives Matter", chanted "Hands up, don't shoot".
Officer Brentley Vinson, who shot Scott, has been placed on administrative leave pending an investigation - which is standard procedure in this situation.Vinson has been with the force for two years.
The shooting comes just a few months after the fatal shooting of two black men by police officers in Louisiana and Minnesota.