Diamond Reynolds began the Facebook Live stream directly after she says her boyfriend, Philando Castile, 32, was shot at least four times by a police officer in Falcon Heights, Minnesota. The video shows Reynolds and Castile, who are both black, in their car, with a white police officer pointing a gun through the driver-side window. Castile is slumped over in the driver's seat, covered in blood. Reynolds' 4-year-old daughter is in the back seat. Castile died from his injuries.

In the video, Reynolds explains that she and Castile were pulled over for a broken taillight. She says Castile told the officer he had a concealed carry permit and a firearm on him, but when he moved to get his wallet from his pocket, the officer opened fire.

The fatal shooting comes one day after Anton Sterling, a 37-year-old black man, was wrestled to the ground and shot dead by white police officers in Baton Rouge, Louisiana, with the scuffle and aftermath captured on camera. Video of the Sterling shooting went viral as well. Support for the victims' families and outrage has flooded social media, fueling the ongoing #BlackLivesMatter movement across the United States.

Reynolds' Facebook stream is another example of the power that live video can wield.