Salman Muflihi, 23, is now facing attempted murder as a hate crime, sources say. He was originally charged with attempted criminal negligence homicide, assault, forgery and possession of a weapon.
Police said the 36-year-old victim is fighting for his life in critical condition. The victim was last reported to be in a medically induced coma.
After the attack, Muflihi allegedly turned himself in to the district attorney's office and confessed, police sources said.
Muflihi allegedly said he didn't like the way the victim looked at him.
CBS2's Andrea Grymes spoke exclusively with Wellington Chen, a witness to the attack.
"It could've been any one of us," Chen said.
Surveillance video shows the 36-year-old Asian victim walking when his attacker runs up behind, police say, and stabs him.
"Who would've thought that somebody would come up to you out of nowhere, stab you," Chen said.
The attack happened just steps from the Federal Courthouse on Worth and Baxter around 6:30 p.m. Thursday.
The victim's fiancée told CBS2 the victim was out for a walk. Chen was doing the same, taking pictures, when he noticed a man up the street.
"He turned the corner and he come charging up. so quickly. And then, I thought he just shoved the Asian male. And the Asian male turned around and looked at him. So I thought they knew each other so I made nothing of it," Chen said.
Chen snapped a photo, showing the victim still standing, and didn't realize he had witnessed a stabbing until he got home and heard the news.
Police are calling the attack unprovoked, saying no words were exchanged. They believe the suspect is emotionally disturbed.
The victim's fiancée calls him an incredibly kind and modest man from an immigrant family, a graduate of MIT. She can't believe this happened to him.
She says they've generally felt safe living in Manhattan for the last several years, until now. She's just hoping he's able to make a full recovery.
WATCH: CBS2's Cory James Reports After Another Member Of Asian Community Attacked In New York City
"This is very upsetting. We have been seeing so many more attacks on Asians. This is a hate crime. I don't care how you say it," Jenny Low, Democratic district leader in Chinatown, told CBS2's Cory James.
The NYPD said as of Sunday, there have been two prior hate crime incidents this year, but they're only classified as such when words are exchanged. Last year, there were 29 incidents, including 24 that were believed to have been motivated by COVID-19. In 2019, there were only three anti-Asian hate crimes.
"We need the mayor and the police department to put some resources in the Anti-Hate Crime Task Force. I understand that they are sort of volunteering to do that, but without resources they can't do their work. It's like, you have a vehicle and you don't put gas in it and you don't charge it up, they can't run," Low said.
The mayor and others have been speaking out against Asian hate crimes.
"We had a horrible incident yesterday, a horrible act of violence against an Asian-American man out of nowhere. Just pure hatred," Mayor Bill de Blasio said Friday.
Right now, more than 3,000 hate incidents directed at Asian-Americans have been recorded since the start of the coronavirus outbreak, according to one advocacy group.
Some of the recent disturbing incidents in New York City include a Flushing, Queens woman who was violently pushed to the ground, a SoHo woman who was peppered sprayed on the street, and now Thursday's stabbing, which sent another Asian New Yorker to the hospital.
CBS2's Cory James contributed to this report.
for more features.