A Ferguson Police officer who threatened to kill protesters has been taken off duty after a complaint from the Missouri ACLU, the organization announced Wednesday.

The organization tweeted, "SUCCESS! In response to our letter, officer who threatened to kill #Ferguson protesters has been removed from duty," soon after posting a copy of a letter addressed to the Missouri State Highway Patrol. The ACLU's Vanita Gupta tweeted "Highway patrol called. They identified the cop. He will no longer be in ferguson."

In a letter sent Wednesday, the ACLU called on the Missouri Highway Patrol to "identify and remove" an officer featured in the video below. In the video, the officer points a gun protesters and says he'll "fucking kill" one man. When asked what his name is, he replies "Go fuck yourself." While Ferguson protests have had "tense moments," the ACLU argues that the officer's behavior was "from start to finish wholly unacceptable."

In a statement, the St. Louis County Police Department said the officer was with the St. Ann Police Department, and had been relieved of duty and suspended "indefinitely":

The Missouri ACLU has been actively following the events in Ferguson and most recently argued with several groups that the informal curfew issued by law enforcement was unconstitutional. 

This post has been updated.