Russia’s telecom watchdog is launching a fresh assault on the use of virtual private networks (VPN) to access forbidden websites.

According to Russian media outlet Vedomosti, Russia’s Roskomnadzor telecom authority has been pressuring VPN services to restrict their users’ ability to access the tens of thousands of domains on the watchdog’s ever expanding blacklist, on which internationally licensed online gambling sites hold a significant presence.

The use of VPNs isn’t (yet) illegal in Russia, as there are legitimate purposes for which such services are warranted. That said, last November’s decision by Opera Software to cease operations in Russia followed shortly after a meeting with Roskomnadzor officials, who reportedly took issue with the built-in VPN functionality in the latest version of the Opera browser.

That same November, Roskomnadzor blacklisted a Russian VPN service called HideMe.ru. The service’s owner, Markus Saar, claimed he addressed all the violations that earned his site a scarlet letter but Roskomnadzor refused to remove HideMe.ru from the blacklist.