According to police, the 61-year-old victim was out collecting cans and bottles around 8 p.m. Friday when another man shoved him from behind, CBS2's Christina Fan reported.
It happened near the corner of Third Avenue and East 125th Street. Officers are reviewing surveillance video of the assault.
For at least ten seconds, video shows the suspect repeatedly stomping on the victim's head as he was lying motionless on the ground. He is now in serious condition, but was listed as critical when he arrived at the hospital.
CBS2 decided not to show the entire video because of its graphic nature.
Police released pictures of the suspect, asking the public to help identify him. The suspect was last seen wearing a black jacket, black pants, white sneakers and a multi-colored baseball cap.
Neighbors were stunned by the display of violence.
"It's very bad. Very bad for everybody," one East Harlem resident told CBS2's Nick Caloway.
"It's sad, and it's starting to happen more and more and more to the Asian people. I think that had a big part in it," East Harlem resident Dee Gwyn said.
The NYPD is investigating to see if the victim was targeted due to his race. Anti-Asian crimes in the city are up 450% compared to the same time last year, and hate crimes against Asian Americans are skyrocketing nationwide.
"You know, as a New Yorker, it's really hard to watch and to see New Yorkers turning on each other like that," said Jo-Ann Yoo, executive director of the Asian American Federation.
She said more needs to be done to educate communities about racism and people need to calm down.
"I hope people start to develop a longer fuse so that way they don't act," she said.
Back at the scene, Calvin Hunt and his son, Cameron, came to show support for the latest victim, holding signs that read "Asian Lives Matter."
"It was horrifying. I hope he's alright. I pray for him and his family, and I'll let them know that we're going to be behind this 100%. We're going to find out who did it, and if we find them, we're going to make them pay," Hunt said.
Anyone with information on this attack is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-8477 or for Spanish, 1-888-577-4782. Tips can also be sent to the NYPDTips Twitter account or submitted online at NYPDCrimeStoppers.com.
A group of advocates will hold a march in Washington Heights in support of Asian Americans on Sunday. It will begin in Mitchel Square at noon.
CBS2's Christina Fan and Nick Caloway contributed to this report.
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