Castile's death was live-streamed on Facebook by his girlfriend.

Reynolds said Wednesday started out as a typical day of running errands. While the officer, an eight-year veteran of the department, acknowledged he wrote the post, he "said it was a form of sarcasm directed at a person with whom he was electronically conversing on Facebook". Afterward, a Roseville police officer brought Reynolds home. The Dallas shooting took place during a rally to protest the police killings of Castile and one other black man earlier this week.

For Ericka Cullars-Golden, one of hundreds of people protesting the fatal police shooting of a black man in Minnesota, the incident provoked a sadly familiar feeling of shock.

"There's a reflex that has now been developed among African-Americans that you need to pull out your cellphone and capture these things when they happen", says Shaun Harper, a professor at the University of Pennsylvania.

"The police officer stopped us for a busted taillight that wasn't busted", she said, adding they were calmly following the officer's instructions.

On Thursday, Reynolds accused the St. Anthony police of racism and poor treatment of her and her young daughter, who was also in the auto at the time of the shooting.

"I'm going to be strong, but it's my daughter that has to live with this on her little brain for the rest of her life", Reynolds said.

With Castile moaning and gasping for air, the police officer pointed his gun through the vehicle window.

Martin said Brooks will meet with local and state officials and discuss what the NAACP should be doing in the light of Wednesday night's shooting.

She recalled cautioning him to always comply with police, and said she never thought she would lose him.

TIME reports that Castile worked as a cafeteria supervisor at J.J. Hill Montessori Magnet School in St. Paul, where his coworkers said he was a kind and gentle spirit.

"I commend Diamond for putting that video out when she did because if she hadn't done that, we probably wouldn't know the whole truth", she said. We must demand justice.

Ramsey County Prosecutor John Choi said at a Friday news conference that his staff has been working closely with the Minnesota Bureau of Criminal Apprehension on the investigation, which he says is a top priority.