A subway rider is wanted by police after allegedly exposing himself to a teenager on a Queens train and performing a sex act in front of her.

The vile incident occurred just after 4 p.m. on Nov. 2 aboard a southbound A train approaching Beach 98th Street in Rockaway Beach, according to police. That's when the man exposed himself in front of the 19-year-old.

The man, pictured above, then ran off the train, police said. No injuries were reported.

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.