Edward Snowden has used a famous Mark Twain quote to quash rumours he's been killed by agents.

The US whistleblower wrote "the reports of my death are greatly exaggerated" along with a picture of the American writer just days after a mysterious tweet triggered speculation he had been kidnapped or even killed.

The former National Security Agency (NSA) contractor, wanted in the US for spilling state secrets, currently has asylum in Russia granted by Vladimir Putin .

Rumours have been circulating about Snowden status (
Image:
Reuters)

In the 1890s American writer Mark Twain – real name Samuel Clemens – was blighted by rumours that he was gravely ill and on his deathbed.

But those spreading the information had mixed up the novelist with his cousin James Ross Clemens.

When reporters contacted Twain to ask about his health, he replied: “The report of my illness grew out of his illness. The report of my death was an exaggeration.”

Referring to the suspicious messages that appeared on Snowden's Twitter account, his lawyer Anatoly Kucherena said: "I can authoritatively say that he is alive and well, he is living in Russia and is busy with his favourite work.

"Of course, there probably are people interested in speculating on this matter who have been doing this for the last several years."

He claimed without further explanation that "the appearance of certain codes in his Twitter does not mean that he is in danger of some sort.

"This is an attribute of his work and there is nothing bad about it."

Anatoly Kucherena, the lawyer of the US intelligence leaker (
Image:
Getty Images)

One message sent out on Snowden's account read: "It's time."

The second carried 64 characters of code. Both were then deleted.

In 2013, computer geek Snowden started revealing classified documents pertaining to mass surveillance practices carried out by US authorities around the globe.

The same year, Russia granted the whistleblower temporary asylum for one year.

In August 2014, Snowden received a three-year residence permit to live in Russia.

Brazil-based Guardian reporter Glenn Greenwald (
Image:
Getty Images)

In the United States, he faces up to 30 years in prison on charges of espionage and theft of government property.

Kucherena has represented Snowden since 2013.

Glenn Greenwald, a journalist who helped Snowden to leak details of the secret US data, also said the whistleblower was fine.

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