The e-mail service used by National Security Agency (NSA) leaker Edward Snowden is suspending operations. And they can't tell us why - although this cryptic post heavily suggests it has something to do with a government request for information:

I have been forced to make a difficult decision: to become complicit in crimes against the American people or walk away from nearly ten years of hard work by shutting down Lavabit. After significant soul searching, I have decided to suspend operations. I wish that I could legally share with you the events that led to my decision. I cannot. I feel you deserve to know what's going on — the first amendment is supposed to guarantee me the freedom to speak out in situations like this. Unfortunately, Congress has passed laws that say otherwise. As things currently stand, I cannot share my experiences over the last six weeks, even though I have twice made the appropriate requests.

FYI, Lavabit was created by a group of Texas programmers who had concerns about privacy protections in Gmail. Snowden used their encrypted e-mail service, and the 6-week timeframe suggests that Snowden's own account might be at issue. It seems likely that the government has requested data under a statute that allows them to enforce a gag order, such as the Patriot Act and the FISA Act. Civil liberties groups have argued that these gag orders violate the First Amendment.