Twitter Nabs Subway Flasher

When a flasher started openly fondling himself on a Boston subway last week, fellow passenger Nay Khun took the issue to Twitter. Khun snapped and immediately tweeted a photo of the flasher, writing: "pervert on the 2nd car of the red line ... help me report him." Thanks in large part to Khun's photo, transit police found the man two days later and arrested him for open and gross lewdness.

The flasher is a known offender, CNN learned from police, who praised Khun's quick thinking when he saw the man "fidgeting with his crotch." Khun "felt the way to leverage a police response was to use Twitter, and in this case it worked quite successfully," said the local police chief. (More flasher stories.)