Hacking group Anonymous launched a demonstration that temporarily shut down four San Francisco subway stations yesterday.

The protest revolved around claims of police brutality and free speech after the Bay Area Rapid Transit (Bart) commuter train service shut down mobile phone networks in some stations last week to stop demonstrators organising a protest over the fatal shooting of a man by police last month.


Last week, BART reportedly cut off power to its wireless nodes after

learning that demonstrators planned to use social media and text

messaging to organize a protest against the shooting, a move that has

troubled civil libertarians.

Anonymous, a loosely knit group that has attacked financial and

government websites, had called for protesters to descend on the

station at 5pm and local media widely reported the plan.

Would-be protesters were encouraged to download software for

short-range mobile-to-mobile messaging, in case the in-station networks

were shut down again.

Bart said a website for its users, mybart.org , had been hacked

over the weekend, and contact information from at least 2,400 people

had been stolen.

The shutdown of the wireless towers helped raise questions about the

role that social networks are playing in helping people, from Egypt to

London, organize online. In the U.S., with its history of free speech,

critics are saying BART's move was unconstitutional.

"This was a complete silencing of the people," one protester told media.

A few dozen people turned out for Monday's rush hour action, which ended when authorities shut down the Civic Centre station.

Some pretended to speak on their phones to taunt officials.

Later, three other stations were briefly closed, reportedly due to crowding.

Police said there were no arrests, although officers arrived dressed in riot gear.

Mobile phone service was left on in the station during the demonstration and some protesters took that as a sign of victory.