The fatal shootings of two black men in less than 24 hours by US police, both captured on mobile phone video and circulated on social media, have sparked controversy and triggered further protests about alleged aggressive police tactics and racial profiling.
On Wednesday night, Philando Castile (32) was shot in the largely middle-class St Paul suburb of Falcon Heights, Minnesota after he was stopped by a police officer for a broken light on the back of his car.
His girlfriend, Diamond Reynolds, broadcast the bloody aftermath of the confrontation live on the social media website as her partner lay dying.
Mr Castile informed the officer that he had a weapon in the car that he was licensed to carry, according to Ms Reynolds on her live broadcast, and that he was reaching for his wallet when he was shot.
The young black man is seen moaning and slumped over, his right side soaked in blood on the video, with the police officer still pointing his gun.
“Ma’am, keep your hands where they are,” the officer shouts at Ms Reynolds on the video. “I told him not to reach for it! I told him to get his hands up.”
His girlfriend is heard on her video telling the officer that he shot four bullets into Mr Castle as he was “just getting his licence and registration”.
Mr Castile, who worked as a school cafeteria supervisor, died later at a Minneapolis hospital.
Ms Reynolds said that she recorded the aftermath of the shooting to highlight police discrimination against African- Americans. She said he had no criminal record.
“I didn’t do it for pity. I didn’t do it for fame. I did it so that the world knows that these police are not here to protect and serve us. They are here to assassinate us. They are here to kill us because we are black,” an angry Ms Reynolds told reporters.
Early on Tuesday, Alton Sterling (37) was shot by police in Baton Rouge, Louisiana after two police officers responded to a complaint about an armed man threatening people with a gun outside a food mart and grocery shop. Two mobile phone videos partially captured the encounter.
The first video, released hours after the shooting, shows one officer tackling Mr Sterling to the ground, then the two officers struggling with him on the ground before there is a shout and gunshots ring out.
A second video, recorded by the shop’s owner, Abdullah Muflahi, and posted online later in the day, shows, from a closer angle, one officer kneeling beside Mr Sterling and the other officer straddling his legs.
Mr Sterling’s hands are not visible and the camera pans to the right as the shots ring out.
The camera then pans back to show Mr Sterling on the ground with a bloodstain on his chest and the officer who had been on his legs lying on the ground with his gun drawn, pointing it at the man.
Mr Muflahi later told the New Orleans Advocate, the local newspaper, that the police were "really aggressive with him from the start".
He said Mr Sterling’s hand was not near his pocket during the confrontation and that afterwards he said one officer retrieved a gun from his pocket after he was shot.
Mr Sterling was pronounced dead at the scene of the shooting. He had a criminal record that included burglary, domestic abuse and illegally carrying a weapon.
The killings of both men led to protests in Louisiana and Minnesota as demonstrators from the Black Lives Matter movement tied these latest police shootings to a pattern stretching back to past high- profile incidents of alleged police brutality in Ferguson,
, and Staten Island, New York.
Mr Castile is at least the 509th American to be shot and killed by police this year, according to the Washington Post, which maintains a database of police killings. He is one of 123 black Americans killed by police this year.
Louisiana governor John Bel Edwards said on Wednesday that the US justice department's civil rights division, which investigated the fatal August 2014 police shooting of black man Michael Brown in Ferguson, would take the lead in the investigation into the shooting of Mr Sterling.
The two officers involved, Blane Salamoni and Howie Lake, have been placed on administrative leave.
In Minnesota, governor Mark Dayton said he had spoken with White House chief of staff Denis McDonough and asked that the justice department launch an "immediate independent" investigation into the killing of Mr Castile.
The governor made the call hours after nearly 200 people gathered outside his home in the early hours of Thursday morning, shouting: “No justice, no sleep”– a chant that has become synonymous with the Black Lives Matter movement.