A demonstrator wears a mask during a protest inside the Bay Area Rapid Transit (BART) Civic Center station on August 15, 2011 in San Francisco, California. The hacker group “Anonymous” staged a demonstration at a BART station this evening after BART officials turned off cell phne service in its stations last week during a disruptive protest following a fatal shooting of a man by BART police. (Photo by Justin Sullivan/Getty Images)

Bay Area Rapid Transit (BART) police push back a demonstrator that is taunting them at the Civic Center station on August 15, 2011 in San Francisco, California. (Photo by Justin Sullivan/Getty Images)

A Bay Area Rapid Transit (BART) worker (L) tries to move demonstrators that are trying to keep a train from leaving the Civic Center station on August 15, 2011 in San Francisco, California. (Photo by Justin Sullivan/Getty Images)

Demonstrator Tom Comitta pretends to talk on a telephone during a protest inside the Bay Area Rapid Transit (BART) Civic Center station on August 15, 2011 in San Francisco, California. (Photo by Justin Sullivan/Getty Images)

A passenger is surrounded by Bay Area Rapid Transit (BART) police officers as she watches a demonstration on the platform at the Civic Center station on August 15, 2011 in San Francisco, California. (Photo by Justin Sullivan/Getty Images)