A breach of AT&T that exposed “nearly all” of the company’s customers may have included records related to confidential FBI sources, potentially explaining the bureau’s new embrace of end-to-end encryption.

The FBI admitted that they believe hackers broke into AT&T's syems last year to steal months of call and text logs. According to a document reviewed by Bloomberg, the FBI scrambled to contain a disaster,

Hackers who breached AT&T's systems may have handed criminals a roadmap to FBI informants, stealing call logs that could unravel investigations and jeopardize lives, according to alarming new details revealed Thursday.