The Russian lawyer of Edward Snowden said Tuesday that the fugitive US intelligence leaker has feared for his life since reading of explicit threats against him by unnamed Pentagon officials.
"There are real threats to his life out there that actually do exist," Snowden's lawyer Anatoly Kucherena told Russia's state-run Vesti 24 rolling news channel.
"These statements call for physical reprisal against Edward Snowden," Kucherena said.
The former National Security Agency contractor is wanted by US authorities on treason charges for disclosing details of a vast Washington intelligence operation that monitored millions of phone calls and emails across the world.
Snowden received temporary asylum in Russia in August -- a move that infuriated the United States and was a key factor behind President Barack Obama's decision to cancel a summit with Russia's Vladimir Putin last year.
The 30-year-old has remained in hiding but is believed to be living in the Moscow area and learning Russian. Kucherena recently said that Snowden has also been working from home as an IT adviser for a major local website.
The Russian lawyer on Tuesday appeared to be referring to an article posted last week by the popular US online website BuzzFeed entitled "American Spies Want Edward Snowden Dead".
The article quoted one Pentagon official as saying: "I would love to put a bullet in his head."
"In a world where I would not be restricted from killing an American, I personally would go and kill him myself," a current NSA analyst was further quoted as saying.
Kucherena said Snowden is constantly accompanied by security guards and is considering additional security measures.
"Edward is treating these as real threats to his life and wellbeing," the Russian lawyer said. "Today, it might not be enough to have private guards."
Kucherena added that he planned to ask US authorities to look into the publications and possibly ask the media outlets to identify their sources by name.
"We think that the US government must take note of such statements," the lawyer said.
"The people who make extremist statements do so while wearing a mask -- they do not reveal their identities.
"We will ask for these people's masks to come off. We must know who this NSA officer is, who issues orders about ways to eliminate Edward Snowden."
Snowden's legacy has been mixed in the United States.
It has prompted Obama to announce a review of intelligence practises last week that included an end to the highly controversial monitoring of calls of leaders of allied nations -- except for special cases.
The revelation that the NSA had tapped the mobile of German Chancellor Angela Merkel proved especially embarrassing for Obama due to the strength of their relationship and Germany's importance to the United States.
Influential US publications such as The New York Times have added to the debate by suggesting that Snowden be either offered amnesty or a plea bargain allowing his safe return home.
The fugitive's lawyer said Snowden was especially concerned by comments from a US Army intelligence officer that outlined a specific scenario under which the leaker could be discreetly poisoned.
The unnamed army officer told BuzzFeed that Snowden could be "poked" on his way home from buying groceries by a passerby who is actually a US agent.
Snowden "thinks nothing of it at the time (and soon) starts to feel a little woozy," the US intelligence officer is quoted as saying.
"And the next thing you know he dies in the shower."
Kucherena said he did not think the US Army officer's statement was "a simply tongue-and-cheek remark for the media".
"Such statements, of course, Edward treats as a real threat to his life because he lives a normal life and visits stores and goes outside," Kucherena said.