Massive pillow fight at Justin Herman Plaza

February 15, 2010 2:25:46 PM PST
Thousands of people celebrated what's become a Valentine's Day tradition in San Francisco Sunday night.

The all-out pillow fight took place at Justin Herman Plaza.

When the clock at the Ferry Building struck 6 p.m., the feathers started flying.

The event began a few years ago as a flash mob, organized through text messages.