As US officials began to realise that Russian Federation was trying to sabotage the 2016 presidential election, the informant became one of the CIA's most important - and highly protected - assets.
It cited unnamed Russian law enforcement officials as saying Moscow had initially opened an investigation into his suspected murder in Montenegro before concluding he was alive and living overseas.
USA network NBC meanwhile claimed to have found a man living in the Washington area who - according to two Federal Bureau of Investigation sources - matched the descriptions of the man in the CNN report.
Since then he has not been heard from, but real estate records show that an Oleg and Antonina Smolenkov purchased a house in Stafford, Virginia, about 40 miles (65 kilometers) south of the U.S. capital June 5, 2018. He did not say why. Kremlin spokesman Dmitry Peskov said Smolenkov had worked in the Russian presidential administration but had been fired in 2016-2017. The reports of Smolenkov being a USA spy are "pulp fiction", he added.
Smolenkov did not have direct access to Putin, Peskov added, declining with a laugh to confirm whether he had been a USA agent or not.
"All these speculations in USA media outlets about urgently extracting him, from whom he was saved and so on - this, you know, is a kind of a "Pulp Fiction", said Peskov. "No, I can not confirm this because I do not know whether he was an agent or not". "A USA official said before the secret operation there was media speculation about the existence of such a covert source, and such coverage or public speculation poses risks to the safety of anyone a foreign government suspects may be involved", Sciutto acknowledges.
According to CNN, the Russian spy had been a crucial asset for the United States government, having access to Russian President Vladimir Putin.
A Kremlin spokesman said he did not know if Mr Smolenkov was a spy and that the extraction reports were "fiction".
All this speculation in the USA media about who urgently extracted who and who saved who from who, that's all, as you understand, more of a pulp fiction kind of genre.
The Times reported that the informant was crucial to the U.S.'s understanding of the scope of the Russian government's interference in the 2016 election, and the extraction "effectively blinded" American intelligence officials to "the view from inside Russia as they sought clues about Kremlin interference in the 2018 midterm elections and next year's presidential contest".
Russian reports said Mr Smolenkov had worked for Yury Ushakov, a senior aide to President Putin.
Later on Tuesday, Russia's office for presidential affairs said it had not employed Smolenkov.
The disclosure to the Russians by the President, though not about the Russian spy specifically, prompted intelligence officials to renew earlier discussions about the potential risk of exposure, according to the source directly involved in the matter.
"I have never seen this man, have never met him, and have never monitored his career or movements", Mr Lavrov said.
Lavrov said on Tuesday that nobody had divulged any secrets to him at the meeting with Trump.