That means the names, home addresses, email addresses and passwords of BART police officers have been made available, according to CNET. More than 100 officers had their personal details listed, says Sophos.
"These people are criminals and we're going to forward this information to the FBI," BART's union president Jesse Sekhon told the San Francisco Chronicle Wednesday.
Anonymous denied responsibility. "The leak today of BART officer data could be the work sanctioned by those who truly support Anonymous, or agent provocateurs," said a recent tweet from the hacker collective's Twitter account. "Stay skeptical."
A separate post from the group pointed out that Anonymous isn't a single coherent group of hackers. However, it added this note of self-justification: "If the media paid more attention to peaceful protests and general social unrest, hackers would be far less inclined to do things such as leaking data just to get the attention of the press."