An encrypted email service Lavabit?alleged to be used by?U.S. whistleblower?Edward Snowden?abruptly shut down.

U.S. whistleblower Edward Snowden

The founder of Lavabit Ladar Levison said in a statement on the company website that he refused to "become complicit in crimes against the American people."

"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," said Levision.

"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," Levison wrote.

"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," Levison continued.

"This experience has taught me one very important lesson: without congressional action or a strong judicial precedent, I would strongly recommend against anyone trusting their private data to a company with physical ties to the United States."

The former U.S. National Security Agency contractor, who has been charged with espionage for revealing the secret U.S. electronic surveillance program Prism, left Moscow's Sheremetyevo international airport on August 1st for he was granted one year asylum by Russia.

Snowden arrived at Sheremetyevo international airport on June 23, where he was stranded for six weeks after the U.S. revoked his passport.

U.S. President Barack Obama canceled his meeting with Russian counterpart Vladimir Putin in September over Kremlin's decision to grant Snowden a temporary asylum.