The information came from a Crime Stoppers tip received shortly after the video was released on Tuesday.
The assault is believed to have occurred early in November 2018 on a train in New York City -- but police still aren't sure where or exactly which train.
Police believe they know the identity of the victim and he lives down south, but they are still waiting to question him. They said he went to the hospital after suffering significant injuries but never reported it to police.
Someone sent Crime Stoppers a link to the video, which then distributed it. The video of a young man being attacked on a subway train is graphic in nature.
It appeared to have been shot on cellphone by someone who may have helped orchestrate the attack.
The victim suffered kicks to the head and blows to the face, and was so helpless he was barely able to plead for mercy or shield himself from the beating.
Police are still working to determine what led to the beating and why the victim wouldn't have called police.
NYPD Chief of Detectives Dermot Shea tweeted out video of the savage attack Tuesday afternoon.
"I thought what every New Yorker thinks," said Shea. "This is our city. And this should not happen."
One challenge for investigators is that only the victim's face is seen in the video.
The attacker's face is never seen, just their hands and sneakers.
"Just a heinous act. Anyone that sees this video is disturbed by it," said Shea.
Anyone with information in regard to this assault is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
The public can also submit their tips by logging onto the CrimeStoppers website at WWW.NYPDCRIMESTOPPERS.COM, on Twitter @NYPDTips or by texting their tips to 274637 (CRIMES) then enter TIP577.
All calls are strictly confidential and anonymous.
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