Marc Mathieu, 36, allegedly repeatedly attacked Narayange Bodhi, a Sri Lankan immigrant on a northbound No. 1 train, last Friday.
A witness to the assault told The New York Post the attack was racially motivated.
Witness George Okrepkie, 56, said Mathieu approached Bodhi and screamed, “You motherf–king Asian!” and pummeled him.
“All of the sudden, the guy was just on top of the elderly man doing a stabbing motion, just hitting him over the head,” Okrepkie said. “Within seconds, blood was all over the [victim].”
Okrepkie said he tried to intervene.
He told New York Daily News, “I was in a state of shock.”
“It’s an incredibly disgusting attack on an Asian American,” Okrepkie continued. “I tried to go after the assailant but he took off.”
Mathieu also has been charged with felony assault.
New York City Police Commissioner Dermot Shea said the suspect was found after an “exhaustive video canvass” by NYPD Transit detectives, according to WPIX, the CW-affiliated station in New York.