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A Texas police officer has been fired after he was recorded on video threatening a teen and using profane language.
Disraeli Arnold, an officer in Hurst, Texas, was recorded in November running to assist an officer as he subdued a teenager, ultimately kneeing the teen in the back of the head while yelling and threatening him.
The teen's mother, Kelly Pope, didn't object to her son being arrested, just the force used to take the teen into custody.
"He [her son] knows that he handled it badly at first, that he should have been a little more cooperative. But, you know, the second officer -- there was no reason for it," Pope said in November. "He (Arnold) comes up at a jolting sprint, kneed him in the back of the head and, as you can see on the video, he says, 'If you move I'm going to [expletive] kill you.'"
While the teen was in custody and being escorted to a police car, Arnold then paraded in front of the teen's friend, who was recording the arrest, and said, "You got it on tape? Arnold, 654!"
Using the video as evidence, the teen's mother filed a complaint with the Hurst Police Department that led to an internal affairs investigation. The mother said she hoped the officer would either turn in his badge or be fired.
Dashcam video released several days later showed the teen, prior to Arnold arriving at the scene, arguing with Officer Miguel Jimenez and resisting arrest -- a offense for which he was charged.
On Thursday, Hurst police said Arnold was "indefinitely suspended for violations of Hurst Police Department General Orders and Civil Service rules relating to his actions on Nov. 20, 2012" and "an internal affairs investigation was conducted for violations ... to include the unnecessary use of force, being disrespectful to a citizen, and the use of indecent, profane, or harsh language in the performance of official duties."
Despite Pope's claim of excessive force, the internal affairs investigation determined the amount of force used by Arnold was reasonable since he believed Jimenez was struggling to subdue the teen.
The investigation did find, however, that Arnold was disrespectful to a citizen and "used indecent, profane, and harsh language in the performance of his official duties, and conducted himself in a manner which brought discredit to himself and the Hurst Police Department."
"You can't help but be embarrassed -- not only for the officers that work in our department, but for anybody in the law enforcement profession," Hurst Assistant Chief Steve Niekamp said in November. "You just expect when an officer shows up, they're going to be in charge. You don't want the foul language, anything that looks like it might be overreaction. You just want to be professional, calm and in control of the scene."
Prior to the department's latest ruling, Arnold had been placed on administrative leave.
Arnold had been with the department for four years and, according to a performance assessment and disciplinary file released by Hurst police after the incident, he met or exceeded police standards in nearly every assessment. The document also noted in May, 2010, that "Officer Arnold's enthusiasm may make him overzealous at times, which can cloud his judgment when it comes to policy, procedure and tactics. Sometimes he needs to step back and see the big picture and risks involved."
Arnold has 10 days to appeal the termination.
NBC 5's Scott Gordon contributed to this report.