Another brutal video of police violence surfaced on Wednesday, this time from New York City. The incident took place over the summer, when 17-year-old Marcel Hamer was walking down the street in Brooklyn. According to lawyers for the family, which is suing the officer, Hamer was walking home from school around 3:30 p.m. smoking a cigarette when he was confronted by a plainclothes police officer.

The video, taken by a friend of Hamer, begins with the young man lying on the curb underneath the rear bumper of a parked car. The police officer, who apparently suspected the cigarette contained marijuana, stands over Hamer as he pleads, “Mister, it was just a cigarette, sir.” The cop then appears to knock Hamer unconscious and handcuffs him.

Here’s more a more detailed account of the encounter from the Brooklyn Paper.

A video of the incident picks up with Hamer lying in the gutter pleading with the officer to lay off as the cop holds him by the hand and orders, “Turn around.”

“Mister, it was just a cigarette, sir,” Hamer says, repeating, “It was just a cigarette.”

He does not roll over.

Teens, apparently friends of Hamer’s, hover nearby and the officer turns to one, still holding Hamer, and threatens him.

“Do you wanna get f—– up?” the cop says.

The moment of the apparent knockout blow is partially obscured in the footage, but the officer appears to punch Hamer in the face with his left hand, prompting protests from Hamer’s friends.

“Yo, you wiling!” one teen says to the officer.

“Yeah, get it on film,” the cop retorts.

The officer then repeats his order for Hamer to “turn around,” but Hamer is lying completely prone.

“You knocked him out!” a female friend yells.

“Wake up, Cello,” another friend says.

“If what happened on this video was reversed and Marcel assaulted this officer in the same exact manner, Marcel would be prosecuted, and this officer should be prosecuted for what he did,” the family’s attorney, James Ross, told the Brooklyn Paper. “Hamer, now 17, has suffered from headaches, dizziness, and memory loss since the incident, his mom said.” “He is always complaining of headaches and he cannot remember things,” the young man’s mother, Mary Hamer, told the Brooklyn Paper. “He used to be pretty sharp, and now I am helping him.”