The email service apparently used by NSA whistleblower Edward Snowden has abruptly gone offline, with its owner citing legal reasons preventing him from explaining the action.
Called Lavabit, the email service claimed to offer advanced security features not found on alternatives and had 350,000 users; Ladar Levison, owner of the service, said he would rather close his company than become complicit in "crimes against the American people".
Writing on a landing page which is all that remains of the service, Levison said: "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.
Levison said after "significant soul searching" he has decided to suspend operations, adding: "I wish 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 his legal situation currently stands, Levison explains, he cannot share his experiences of the last six weeks, despite claiming to have twice made "the appropriate requests".
Snowden, who leaked documents describing the NSA's Prism surveillance system used to monitor the communications of web users on a massive scale, is believed to have been a Lavabit user after an email from an address in his name invited reporters to a press conference at Moscow's Sheremetrevo Airport in mid-July while he was camped-out there awaiting asylum.
The move was branded as unprecedented by privacy advocates, with lawyer Kurt Opsahi of the Electronic Frontier Foundation telling the Guardian: "I am unaware of any situation in which a servicer provider chose to shut down rather than comply with a court order they felt violated the Constitution."
Levison's decision to close Lavabit comes on the same day that encrypted communication service Silent Circle chose to shutter its own email service, Silent Mail, stating: "we see the writing on the wall."
In a blog post on 9 August, Silent Circle CTO and co-founder Jon Callas said: "We've been thinking about this for some time, whether it was a good idea at all. Today, another secure email provider, Lavabit, shut down their system...we see the writing [on] the wall, and we have decided that it is best for us to shut down Silent Mail now.
"We have not received subpoenas, warrants, security letters, or anything else by any government, and this is why we are acting now."
Callas said he and his company had been "debating this for weeks" and had changes planned to start from 12 August, but admitted that it "is always better to be safe than sorry...with your safety we decided that the worst decision is always no decision."
Silent Circle will continue to offer its end-to-end encrypted phone and text services but explains that, while more secure than others, Silent Circle's email service can never be trully secure because it must use the same standard internet protocols as all other such services. "There are far too many leaks of information and metadata intrinsically in the email protocols themselves," Callas said, concluding: "Silent Mail was a good idea at the time, and that time is past."