The attack happened Friday around 3:30 a.m. in the area of W. 116 St. and Lenox Avenue.
According to police, the suspect, identified as 43-year-old Norton Blake, is seen in the video swinging an umbrella at the woman.
When the woman used her cane to try and defend herself, Blake allegedly took it and used it against her, hitting her around 50 times for over two minutes, police said.
EMS transported the victim to NYC Health + Hospitals / Harlem in stable condition. Blake fled the station, police said.
It’s unclear what led up to the attack. No arrests have yet to be made.
According to the most recent police department statistics, transit crime is down 4.5% this year compared to last.
Anyone with information in regard 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). The public can also submit their tips by logging onto the Crime Stoppers website at https://crimestoppers.nypdonline.org/, or on Twitter @NYPDTips.
All calls are strictly confidential.