Yesterday, the Bay Area Rapid Transit system had word that a protest in the system was planned to rally against a BART police shooting last month in which a man was killed. To nip any protest in the bud, BART shut down cell phone service on the train platforms. From the Bay Citizen:

The commute went on without a hitch, but no one could get cell phone service on the platforms or the trains. KTVU reported that BART's media relations department suggested cutting off the cell service during the protests.

BART police Lieut. Andy Alkire told Bay City News that while it was unusual to kill cell phone service, it was "a great tool to utilize for this specific purpose" with the agency facing a potentially volatile situation.