Chicago: Racial tensions soared as officials released a graphic video of a police officer shooting a black teen, shortly after he was charged for the death.
The dashcam video shows officer Jason Van Dyke open fire 16 times on Laquan McDonald, 17.
Shot from an approaching cruiser, it shows McDonald run down the middle of the street towards a cruiser, hitch up his pants and then start to walk away from Van Dyke and his partner.
His body then spins and strikes the pavement. McDonald lifts his head, moves an arm and then a cloud from another gunshot rises up from his chest as he lays in a fetal position.
He does not move as an officer enters the frame for just long enough to kick a knife away from his prone hand.
None of the officers approach McDonald to try to help him as he bleeds out on the street, writhing once in the remaining minute of video.
Prosecutors said Van Dyke opened fire just 30 seconds after his cruiser pulled up to the scene and six seconds after stepping out of it.
"It is graphic, it is violent, it is chilling," Cook County State's Attorney Anita Alvarez told reporters after charging Van Dyke with first degree murder.
"To watch a 17-year-old young man die in such a violent manner is deeply disturbing and I have absolutely no doubt this video will tear at the hearts of all Chicagoans."
McDonald -- who police said was holding a knife when he was shot and had earlier slashed the tires of a police cruiser -- made no threatening gestures to justify the use of deadly force, Alvarez said.