An elderly man who was the victim of a violent robbery in Manhattan has died.

Young Kun Kim, 87, was attacked inside a Citibank on Mother's Day on the Upper West Side.

He was a political science professor at the CUNY Graduate Center.

Surveillance video shows Kim being repeatedly punched and kicked, allegedly by 50-year-old Matthew Lee.

Lee was arrested on Thursday. He now faces second-degree murder and robbery charges. He says even though the attack was caught on video, he doesn't remember it.