Russian authorities fined Facebook and the messaging app Telegram on Thursday for failing to remove banned content, a move that could be part of growing government efforts to impose stricter control over social media platforms amid political dissent.

A Moscow court fined Facebook a total of roughly $236,000 and Telegram $139,000. It wasn’t immediately clear what type of content the platforms failed to take down.

It was the second time both companies have been fined in recent weeks. On May 25, Facebook was fined $362,000 for not taking down content deemed unlawful by the Russian authorities. A month ago, Telegram was also ordered to pay $69,000 for not taking down calls to protest.

Earlier this year, Russia’s state communications watchdog Roskomnadzor started slowing down Twitter and threatened it with a ban, also over its alleged failure to take down unlawful content. Officials said the platform failed to remove content encouraging suicide among children and containing information about drugs and child pornography.

The crackdown unfolded after Russian authorities criticized social media platforms that have been used to bring tens of thousands of people into the streets across Russia this year to demand the release of jailed Russian opposition leader Alexei Navalny, President Vladimir Putin’s most well-known critic. The wave of demonstrations has been a major challenge to the Kremlin.

Officials alleged that social media platforms failed to remove calls for children to join the protests. Putin has urged police to act more to monitor social media platforms and to track down those who draw children into “illegal and unsanctioned street actions.”

The Russian government’s efforts to tighten control of the internet and social media date back to 2012, when a law allowed authorities to blacklist and block certain online content was adopted. Since then, a growing number of restrictions targeting messaging apps, websites and social media platforms have been introduced in Russia.