Update (6:21 p.m.) Several people have been arrested, and media has been kicked out of the Powell street station.
Update (5:53 p.m.) One man has been arrested.
Update: (5:40 p.m.) Protesters blocked fare gates and commuters can no longer access Powell Street station. Everyone has been booted from the station -- including media.
Update (5:30 p.m.) SFPD is at the entrance of Powell Street, saying they will close the gates.They are encircling, warning protesters they will arrest anyone who moves inside their boundary.
Update (5:25 p.m.): Protesters have entered the station chanting "You can't kill us all!" Still, the scene is rather calm.
If you are headed for BART now, good news is there. The trains are still running on time, despite the fact that some entrances to the Powell Street station have been closed.
SF Weekly staff writer Ellen Huet is at the scene and tell us that commuters can still enter the main gates at the station -- but the fare gates are still open.
BART spokesman Jim Allison warned earlier that any protesters who blocked fare gates would be arrested.
Huet tells us that a bunch of police are standing outside the station and a small high school band is serenading bystanders inside the station.
But things could change, so check back here for updates.
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