Graphic Video Released by Chicago Authorities of Cop Killing Black Teenager

A chilling dash cam video was released Tuesday evening of a Chicago cop shooting to death a black teenager.

The long-awaited release came a few hours after the white officer involved, Jason Van Dyke, was charged with first-degree murder in the death of 17-year-old Laquan McDonald, who was shot 16 times in October 2014, authorities said.

Prosecutors said Van Dyke was going to reload his weapon after emptying it, but another officer stopped him. 

The grainy, disturbing video shows the teen running and walking down the middle of a street where officers are gathered. As he crosses diagonally away from them, McDonald spins around as he is shot and falls to the ground.

Read: Chicago Cop is Charged With Murder in Death of Black Teen Who Was Shot 16 Times

An officer kicks something away from him. More officers arrive on the scene, but no one is seen checking on the boy, who moves just a bit, then lies motionless.

Van Dyke was the only officer on the scene to open fire, authorities said.  He is currently being held without bail.

Puffs of smoke rise off the teenager and his body jerks as he is hit by bullets.

Van Dyke has said the teen lunged at him with a knife. Prosecutors said the teen never spoke to the officer and was carrying a pocket knife in his hand, but did not move toward the officer.

“To watch a 17-year-old young man die in such a violent manner is simply disturbing and I have absolutely no doubt that this video will tear at the hearts of all Chicagoans,” said Cook County state’s attorney Anita Alvarez.

Mayor Rahm Emanuel appealed for calm Tuesday.

"I believe this is a moment that can build bridges of understanding rather than become a barrier of misunderstanding," Emanuel said. It is "fine to be passionate, but it is essential that it remain peaceful," NBC Chicago reported.

Read: 'Officer of the Year' Suspended After Throwing Bikin-Clad Teen to Ground, Pulling Gun

Hundreds took to upscale Michigan Avenue Tuesday night Chicago to protest the length of time it took for the officer to be charged and the video to be released.  Demands for the video to be released have been made for more than a year.

The protests appeared to be peaceful, but police did block off part of the trendy thoroughfare of shops and restaurants.

Prosecutors said Tuesday that Van Dyke opened fire 30 seconds after arriving on the scene.

The officer contends he acted reasonably because McDonald was carrying a knife and did not respond to orders to drop it. His attorney, Dan Herbert, told reporters Tuesday his client feared for his safety when he opened fire.

Watch Below: Police Apologize to Family After Cop Shoots Dog in the Head 

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