(Image contributed to the BB Flickr Pool by Bhautik Joshi)
BART temporarily interrupted service at select BART stations as one of many tactics to ensure the safety of everyone on the platform.
Cell phone service was not interrupted outside BART stations. In addition, numerous BART Police officers and other BART personnel with radios were present during the planned protest, and train intercoms and white courtesy telephones remained available for customers seeking assistance or reporting suspicious activity.
Good thing the Bay Area subway system operators are taking a cue from Hosni Mubarak! Because, you know, if an actual riot had occurred, it's not like anyone affected would have had any need to communicate for help or anything.
"BART staff or contractors shut down power to the nodes and alerted the cell carriers,"
James Allison, deputy chief communications officer for BART, told CNET.
CNET's Elinor Mills reports that "The initial statement from BART said the subway system had asked the wireless carriers to suspend the service in the stations, but Allison later said BART itself pulled the plug and notified the providers after the fact."
BART says cellphone service wasn't disrupted outside stations: proof, please?
UPDATE: Coverage in Washington Post and Al Jazeera, CSM. Security researchers Christopher Soghoian and Jacob Appelbaum have filed a FOIA request (PDF Link). Those so inspired may want to file a complaint with the FCC (PDF Link). Here's an EFF post on the matter.