Update Thursday: From the Chronicle, regarding responsibility for yesterday's hack:
Anonymous did not take responsibility for the hacking of the BART police union website. A resident of the Canadian province of Ontario, speaking on behalf of this week's BART protest organizers, said someone using the name Lamalin_5mg offered a link to the leaked police information Wednesday during an Anonymous-hosted Internet relay chat.
"There are really no leaders in the group, but some people did tell her that she should not have done it," said the man, who goes by the pseudonym Crappy Tires.
In an online chat set up by Crappy Tires, someone speaking through the username Lamalin_5mg identified herself as a French girl who taught herself computer programming. She said that although this was her first hacking attempt, she had managed to breach the system in less than four hours.
SF Weekly yesterday spoke through an online chat to the woman who claims to have performed the breach of the BART Police Officers Association web site. Here's a transcript of the conversation.
Original post
The Hacker group Anonymous tweeted a web page of names, addresses, personal emails, and passwords it says are affiliated with BART police officers. About a hundred names appear on the list.
BART Police Deputy Chief Daniel O. Hartwig spoke with KQED's Rachel Dornhelm about the breach. Hartwig said the only information he had was that the web site of the BART Police Officers Association has been hacked.
Audio of his response: