Jon Jones violently bashed his head into a cop car and called an officer a "f***ing nerd" during his arrest on the Las Vegas strip back in September ... new police video shows.
In the footage, Jones -- who was in handcuffs and surrounded by cops following an alleged altercation with his fiancee at a nearby hotel -- was clearly furious with officers, screaming at them relentlessly.
The UFC superstar can be heard in the clip asking why he was being detained ... before he launched a verbal tirade against one of the cops standing next to him.
Jones repeatedly called the man a "nerd" ... asking for his name over and over again. Jones also accused the cop and other officers of embarrassing him on an important night for him (his epic 2013 fight against Alexander Gustafssonwas being inducted into the Hall of Fame).
Video shows Jones got so upset with the police -- he actually slammed his forehead into the hood of the police cruiser he was being held up against.
At that point, officers rushed him away, chastising him for the move.
As we reported, Jones was being arrested after he was accused of getting physical with his fiancee and pulling her hair at around 5 AM at Caesars Palace on Sept. 24.
Jones was ultimately hit with misdemeanor domestic battery and felony tampering with a vehicle over the incident ... though court records showed officials dropped the misdemeanor count against the fighter in December after he pled no contest to a misdemeanor charge of destroying property of another.
As part of his sentencing, records showed the 34-year-old was ordered to stay out of trouble, pay restitution to the victim, and take anger management counseling.
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Jones said shortly after the arrest that he was done drinking booze ... and he later shared a video with his fiancee that appeared to show them being a happy couple.