The brazen attack happened on October 23rd.
Police say the assailant grabbed a 19-year-old woman, lifted up her dress, and fondled her.
Then, they got on the same train where she was able to snap a picture, but he got away.
Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.
The public can also submit their tips by logging onto the Crime Stoppers Website at WWW.NYPDCRIMESTOPPERS.COM or texting their tips to 274637(CRIMES) then enter TIP577.