The NYPD is searching for a man they say sexually assaulted a 20-year-old woman onboard a 6 train in Union Square.

Police say that the victim was on a northbound 6 train at 8 a.m. on Monday, September 25th, when she felt someone's private parts rub up against her buttocks. Though the woman tried to move away, the individual moved with her, according to police.

She finally escaped him when she exited the train at 33rd Street, though she managed to snap this photo of him beforehand, police said.

Police say the man is approximately 35-years-old, with brown eyes, black hair and last seen wearing a dark blue with white stripes collar shirt and carrying a black bag.

Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS or for Spanish 1-888-57-PISTA (74782). The public can also submit their tips by logging onto the Crime Stoppers Website or texting their tips to 274637(CRIMES) then enter TIP577.

All calls are kept strictly confidential.

If you see or experience sexual misconduct in the subway (this includes seeing a masturbator, being groped, being grinded on, etc.), you can report it to the MTA and police on this website. There's also a place for you to upload photos and/or video. Don't let the perverts win.