Transcript for Violent arrest in New York City under police probe
a dramatic police takedown on a New York City street. Witnesses say two men lunged at police officers. Those officers striking those men. The two men fighting back. Then undercover officers suddenly appear and it becomes an all-out brawl. The mayor calling the incident tonight troubling. ABC's whit Johnson with what set this off. Back up. Let's go! Reporter: Tonight, this violent arrest prompting an NYPD investigation. Officers hitting two suspects repeatedly with batons. The wild melee in the middle of an intersection. Watch as one of the suspects actually chases after an officer. Several more officers in plain cloths rushing to assist, taking the man down. An officer cracking his baton on the suspect's head. Then, more baton strikes while the man is on the ground. A witness who shot this video says the officers were defending themselves. Two of them actually lunged at one of the officers. He went for a tackle. Reporter: Police telling ABC news that before the video began, the men were harassing commuters on the stairs of a subway station. They say 36-year-old Aaron griessom took a swing at one of the officers, and that 37-year-old Sydney Williams attacked when the other officer stepped in. And tonight, video surfacing of Grissom appearing to threaten police. Keep Me, police, I'm going to show you what it is. These hands, these hands work. Whit Johnson with us live tonight. And while the mayor called the images troubling, you're learning that the two suspects do have lengthy criminal histories? Reporter: David, that's right. Police say both men have been arrested multiple times before, including several alleged incidents of assaulting officers. David? Whit Johnson with us live tonight. Whit, thank you.
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