Some crimes go unnoticed until they're discovered on surveillance tape. Others are caught in the act by passersby.
A recent incident in San Francisco had both, as a surveillance camera caught vigilantes chasing down a thief within seconds.
Video posted online Friday by SFPD shows a pedestrian taking a bike from a rack before being chased by two other pedestrians. The thief is then tackled to the ground by one of the them, the video shows.
A scuffle ensues among the three, broken up as they're surrounded by two automobiles. As they disperse, one of the chasing pedestrians picks up the bike and re-racks it.
The incident happened Wednesday afternoon in broad daylight, on Harrison Street near Mission Cliffs, a rock climbing gym. SFPD uploaded the video to Twitter two days later, mentioning that the Mission Police District has a "Bait Bike" program in effect to catch thieves in the act.
Bait bike programs are often used by police departments in cities with moderate to heavy bike traffic, including Sacramento.