А Russian lawyer has confirmed the arrests of two Federal Security Service (FSB) officers and a manager at a Russian cybersecurity company on treason charges, and that they are suspected of passing classified information to U.S. intelligence.
Ivan Pavlov, who is representing a fourth suspect in the case, confirmed the charges and the identities of the three men in a phone interview with RFE/RL on February 1. He said that there are more than three suspects in the case, but he refused to identify his client or say whether his client was an employee of the FSB.
Pavlov's remarks were the first independent confirmation of the arrests, which occurred in December.
The growing number of arrests, and a steady stream of leaks in Russian media over the past two weeks, have stoked speculation and offered potential glimpses into Russia's formidable security apparatus, and its possible ties to Russia's shadowy underground hacking networks.
At the time of their arrests in December, Sergei Mikhailov and Dmitry Dokuchayev were officers with the FSB's Center for Information Security, a leading unit within the FSB involved in cyberactivities.
Pavlov confirmed to RFE/RL the arrest of Mikhailov and Dokuchayev, along with Ruslan Stoyanov, a former employee of the Interior Ministry who had worked for Kaspersky Labs, a well-known private cyber-research company, which announced Stoyanov's arrest last month.
The newspaper Kommersant reported that Mikhailov was arrested at a meeting of FSB officers and was taken from the meeting after a sack was put on his head.
The independent newspaper Novaya Gazeta, meanwhile, said that a total of six suspects -- including Mikhailov, Dokuchayev, and Stoyanov -- had been arrested. The state news agency TASS reported on February 1 that two men associated with a well-known hacking group had also been arrested in November, but it wasn't immediately clear if those arrests were related to the FSB case.
There has been no public detail as to the nature of the treason charges against Mikhailov, Dokuchayev, and Stoyanov. The Interfax news agency on January 31 quoted "sources familiar with the situation" as saying that Mikhailov and Dokuchayev were suspected of relaying confidential information to the U.S. Central Intelligence Agency (CIA).
Pavlov told RFE/RL the individuals were suspected of passing on classified information to U.S. intelligence, but not necessarily the CIA.
"We have no information about the CIA" in the matter, he said.
While Russian officials have not commented on the record about the arrests, Russian media, citing anonymous sources, have reported the suspects may be tied to hackers targeting the Russian elite and may have disclosed information related to cyberattacks targeting the U.S. election system.
Last month, U.S. intelligence agencies released a report concluding that Russia orchestrated a hacking-and-propaganda campaign targeting the U.S. presidential election with the aims of undermining the U.S. electoral system.
The effort, the report said, sought to discredit Democratic candidate Hillary Clinton, and help her Republican rival, Donald Trump, who won the contest and took office on January 20.
The sources cited anonymously in the Russian media have not expressly linked the reported accusations against Mikhailov and Dokuchayev to the breaches of U.S. Democratic Party servers.
Novaya Gazeta has reported that there may be links to attacks on electoral systems in individual U.S. states.
Private U.S. cyber-researchers have also added to a growing pile of clues linking the U.S. election intrusions to Russian hacking groups, some of whom, according to Russian media, worked in tandem with security agencies.
The Kremlin has repeatedly denied efforts to meddle in the U.S. election.
President Vladimir Putin's spokesman, Dmitry Peskov, said on February 1 that Mikhailov and Dokuchayev could not have been involved in cyberattacks targeting the U.S. election "because as we have already said, we categorically reject any assertions about the possible involvement of the Russian side in any hacker attacks."
TASS said the arrests revealed on February 1 were two men from the notorious Russian hacking group known as Shaltai-Boltai, Russian for Humpty Dumpty.
The agency quoted a spokeswoman for Moscow's Lefortovo court as saying Aleksandr Filinov and Konstantin Teplyakov had been arrested in November and faced charges of illegally intruding into computer systems.
With reporting by Reuters, Interfax, TASS, RIA Novosti, and RFE/RL's Russian Service