A police officer pointed his gun at 4 unarmed, black teens. Now police are investigating

Ryan W. Miller | USA TODAY

Minneapolis Park Police are investigating officers' actions and a 911 call over an alleged assault that led police to detain four unarmed black teenagers, with one officer pointing his gun at the teens.

Police were called to Minnehaha Regional Park on Tuesday after a 911 caller reported teens with sticks, knives and a possible gun in a backpack, Minneapolis Park and Recreation Board said in a statement Wednesday. The caller also reported the teens were assaulting her boyfriend.

The aftermath of the incident was captured in a Facebook post that has since gone viral with a video and photos of two of the boys in handcuffs in front of a police car. In her post, Brianna Lindell wrote that a young, white male around 17 years old was harassing the boys when she and her partner arrived.

"He was spouting racial slurs at them and aggressing them with a metal trash can lid and saying he had a knife," Lindell wrote in the post. A girl with him was on the phone, she said, presumably calling police.

Lindell said she and her partner walked away, but came back when they heard shouting.

After police arrived at the scene, one officer "did unholster his firearm and point it in the general direction of the four suspects," the park board said.

Officers, who were wearing body cameras, detained the teens, with two in the car and two sitting on the ground initially.

The video shows one of the handcuffed boys shirtless in front of the car. Lindell said he "was begging" for his shirt because of mosquitoes. When her partner threw the shirt to the boy, Lindell said a police officer "jumped out of the squad car and started yelling at us that we were interfering with an arrest."

No weapons were found on the teens, who were ages 13, 13, 14 and 16, the park board said. After the two boys were moved into the police car, an officer at the end of Lindell's video said the boys were not under arrest.

Three of the teens were released at the park; one was a runaway and later released. None of the teens were injured, the park board said.

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Police were investigating the origins and validity of the initial 911 call. Making a false crime report is a misdemeanor in Minnesota.

Park police chief Jason Ohotto and superintendent Mary Merrill requested an independent investigation into the officers' response to "determine that park police policies, procedures and laws were followed," the park board said in a statement.

Brad Bourn, president of the park board of commissioners, called the incident "hard to watch" in a Facebook post Thursday.

"Because of the police involved shootings that have happened here in Minneapolis and around the country in recent years, I, like many of you, was very disturbed by what I saw," he said.

He added that park officials were reaching out to the families of the teens and that the board and superintendent intend to review safety protocols to ensure children are safe moving forward.

Contributing: KARE-TV in Minneapolis. Follow Ryan Miller on Twitter @RyanW_Miller