UPPER WEST SIDE, Manhattan (WABC) -- The search is on for the man who critically injured an elderly man inside a Manhattan bank.
It happened at the Citibank on 96th and Broadway on the Upper West Side.
Police say the suspect walked up behind 87-year-old college professor Young Kun Kim, punched him in the head and then stole the money he was holding.
The suspect fled on foot.
"The first thing I thought was anger," the victim's neighbor, Eric Schwartz, said. "Why would somebody do this? I wish I was there to pick Mr. Kim up, protect him, jump in front of the attacker before he had a chance."
The NYPD released video of the attack.
The victim is currently in extremely critical condition at Mount Sinai Hospital.
"It wasn't hard for him to take his money," bank customer Detria Seabrook said. "He was fighting, fighting for his life. It's really sad that somebody would do that to the elderly people."
Kim was known to eat at the same Upper West Side diner every morning before heading to work as a political science and Asian studies professor who has taught at Columbia University, Hunter College and CUNY.
"This is the most vulnerable person on the planet. And you're attacking him for what? For money. It's just beyond. So I hope they find somebody.," said Schwartz.
The suspect is described as a black man in his mid 40s to early 50s, approximately 5-foot-9 and 150 pounds. He was last seen wearing a dark top with a white shirt underneath, dark pants, dark shoes, a blue cap, large headphones and carrying an umbrella.
"It's disgusting that the people are attacking elderly people," Seabrook said. "Every day, you turn on your television, you see people being attacked. This is ridiculous."
Citibank issued the following statement:
"We are deeply saddened and concerned about this tragic event and our thoughts and prayers are with the victim and his family. We have provided the police with surveillance video and we will continue to do everything we can to assist the investigation of this senseless crime."
Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).