Beware of PERVERTED FLASHER on M/R trains

I got on the 8:20 Manhattan-bound M train this morning at the 4th Ave., 9th Street stop and was sitting down, reading the paper like I normally do. A few stops later, a man came on the train, and stood to the left of me next to the doors. I didn't pay close attention until I saw something in my periphery that was moving. I turned to the left and saw the man's penis sticking out while he rubbed it. He stared at me the entire time. I jumped up and shouted -- WHAT THE F--K ARE YOU DOING? The doors opened and he got out at the Dekalb stop, but stared at me through the doors as the train left the station.

DESCRIPTION: He's an older Hispanic man (mid-40s), with graying hair, wearing army fatigue pants, black boots, a dark shirt, dark hat, and sunglasses. He had something tied around his waist.

I wish I had my camera out so I could take a picture and show it to the police. I've filed reports to the MTA and the police, but who knows if anything will be done.

Please be careful the next time you're on the train and be aware of your surroundings! I'm very upset and traumatized by this experience and hope this never happens to you or a loved one.