police tape
This image shows police tape left at Larpenteur Avenue following the police shooting death of a black man in St. Paul, Minnesota, July 7, 2016. Getty Images/Stephen Maturen

A video of an off-duty white police officer in Lansing, Illinois pinning down a black teen on his lawn and threatening to kill him has gone viral. The cell phone video of the incident, which took place Saturday, shows the officer holding the 15-year-old’s neck, pinning him down with his knees and yelling at him.

While the teen has been identified as Jordan Brunson, the identity of the officer has not been released yet. The video, which was posted on Facebook, was filmed by another 15-year-old boy.

In the footage, the officer can be heard yelling: “I’m going to f------ kill you.”

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Ann Falls, who claimed to be Jordan's cousin, shared the video on Facebook on Monday. The one-and-half-minute video has already been viewed more than 4 million times and shared nearly 70,000 times.

In the video, the officer is heard telling Jordan that he was “trying to figure out what’s going on and you guys are acting stupid.”

On being told by Jordan that he wasn't involved, the officer replied: “I don’t give a f--- who is. Do you understand that?”

“Why are you doing this to me then?” Brunson asked. To which the officer replied: “Because your friend is being a f------ idiot,” referring to the teen who shot the video.

Lansing Police Department, in a statement issued at the time, said Jordan was involved in a fight with another teenager and the off-duty officer detained him "physically" to prevent him from leaving.

“According to reports provided by the off-duty Lansing Police Officer, he discovered a backpack in his fenced-in backyard that did not belong to him. After discovering the backpack and finding a baseball hat and a realistic looking BB gun inside, he encountered a male white juvenile on his property, bleeding from the face. The 15-year-old juvenile stated that he was just involved in a fight in which he was beaten up by several male black juveniles,” the statement said.

According to the police statement, while the officer was speaking to the white youth on his porch, Jordan approached them, also wearing a backpack.

“Both of the juveniles attempted to leave at that point in time. The off-duty officer told them to stay until the arrival of the police. The juveniles refused to stay and attempted to leave, resulting in the off duty officer physically detaining one of the juveniles. The juveniles were turned over to the responding officers upon their arrival,” the statement continued.

Speaking to CBS Chicago, Jordan said he was “scared, but was trying to keep calm at the same time.”

“I wouldn’t expect him to think I was a threat to him,” he added.

Jordan's aunt Lashawnya Brunson said the officer’s behavior was disturbing.

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“Where was his police instinct or his training to find out first what was going on with the young guys?” she said, according to CBS Chicago. “That’s an assault to a child," she added.

Lansing police said they were aware of the video and have launched an internal investigation.