A man has now died after being assaulted on a 6 train last week.
Police say the man seen in this surveillance video got into an argument with 45-year-old James Kutza on the train around 8:30 a.m. Friday.
Police say the suspect later punched Kutza at the 125th Street station, causing him to fall and hit his head on the platform. He was taken to Harlem Hospital, where he later died.
Police also released a sketch of the suspect.