Two encrypted email services shuttered this week, citing efforts to avoid government scrutiny that could threaten users' privacy.
Lavabit, which has been linked to NSA whistleblower Edward Snowden, took the first bullet on Thursday, thus inspiring software company Silent Circle to also shut down its mail feature.
"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," owner Ladar Levison wrote in a company memo.
Without offering specific details, he alluded to a government investigation as his reason for the closure.
Lavabit stepped into the spotlight when Snowden reportedly used the service in early July to email political officials with a request for asylum in Russia. The on-the-run fugitive was not named in Levison's explanation.
"After significant soul searching, I have decided to suspend operations," he continued. "I wish that I could legally share with you the events that led to my decision. I cannot."
Hours later, Maryland-based Silent Circle followed Lavabit's lead by shutting down its own email service; the company's encrypted Silent Phone and Silent Text features are still available.
Referencing Lavabit's decision, CTO Jon Callas took to the company blog to inform customers of the changes.
"We see the writing [on] the wall, and we have decided that it is best for us to shut down Silent Mail now," Callas said. The move, he added, is a precautionary measure; Silent Circle has not yet received any subpoenas, warrants, security letters, or other government notifications.
While there had been talk of phasing out the service, or perhaps continuing it for only existing customers, the company ultimately decided to pull the plug in one fell swoop.
"With your safety we decided that the worst decision is always [better than] no decision," Callas wrote.
CEO Mike Janke confirmed to the New York Times that the Silent Mail server has been destroyed and is gone forever.
For more, see The NSA and the End of Privacy.