Russia’s telecommunications watchdog has instructed banking and payment processors to purge unauthorized online gambling operators from their customer and client lists.

On Monday, the Izvestia news agency reported that the Roskomnadzor regulatory body had sent letters to Russia’s largest bank Sberbank and payment processors including Skrill and Yandex ordering them to review their client records to ensure compliance with Russian gambling laws.

Roskomnadzor’s missive comes three weeks after Skrill and rival Qiwi found their websites temporarily added to the agency’s growing blacklist due to links to unauthorized gambling sites. Both sites managed to avoid a permanent shutdown order by cutting ties to unapproved gambling operators.

Russia’s anti-online campaign is being pursued on multiple fronts. Last week, the deputy chairman of the state Duma’s committee on constitutional legislation asked both Roskomnadzor and the state prosecutor for a legal opinion of mobile telecom firms’ involvement in unauthorized gambling financial transactions.