A Moscow court on Thursday sentenced the ringleader of the Shaltai Boltai hackers group to two years in prison.
Vladimir Anikeyev was handed the two-year sentence after pleading guilty to hacking, the Interfax news agency reported. The proceedings, which have been shrouded in mystery, were held behind closed doors.
Anikeyev was detained last year alongside several other suspected hackers, including two top FSB officials working on cyber-security and a former employee of the Kaspersky Lab cybersecurity company.
The timing of the detentions led to speculation that the notorious hacking group had colluded with members of the FSB in a blackmailing scheme which went awry.
The Shaltai Boltai hackers collective, also known as Humpty Dumpty, has gained notoriety in recent years for leaking emails and correspondence that has embarrassed public figures with links to the Kremlin.