FERGUSON, MO - WARNING: Video content contains profanity that may be obsessive to some viewers.
Officials say a police officer who was part of the effort to keep peace during protests in Ferguson, Missouri, has been suspended for pointing a semi-automatic assault rifle at demonstrators, then cursing and threatening to kill one of them.
A protester captured the exchange on video that has been posted to YouTube and several other websites.
St. Louis County police spokesman Brian Schellman says the incident involving an officer from the St. Ann Police Department happened late Tuesday. His name hasn't been released.
The video shows an officer in a dark-colored uniform with his rifle raised walking across a street at night, aiming it at people and swiveling the gun back and forth.
"Oh, my God. Gun raised, gun raised…gun pointed," an unseen male protester says on the video
"My hands are up, bro, My hands are up," another man says.
"I will f---ing kill you. Get back, get back," the officer says.
"You're going to kill him?" one man asks.
"What's your name,sir?" a man asks the officer.
"Go f--- yourself," the officer replies
"Hello, officer go f---- yourself," the demonstrator says.
The video shows a county police sergeant in a khaki uniform using his hands to guide the officer holding the rifle away and gets him to lower the gun. However, a second video shows the same officer continue to raise his rifle at protesters -- and the sergeant again intervenes and has him to lower the gun and move along.
Schellman says the county police sergeant took immediate action, telling the officer to lower the weapon and escorting him from the area. The officer was suspended indefinitely.
The protest was among many in Ferguson since Aug. 9, when 18-year-old Michael Brown was shot and killed by a police officer.
WARNING: These YouTube videos contain profanity:
Video of the officer as he is led away by other cops and continues to aim his gun at the crowd: