Russian authorities are suing five social media platforms for allegedly failing to delete posts urging children to take part in illegal protests, the Interfax news agency cited a Moscow court as saying on Tuesday.

Twitter, Google, Facebook each have three cases against them, with each violation punishable by a fine of up to 4 million roubles (around 54,000 dollars), and cases have also been filed against Tiktok and Telegram, the report said.

The cases were opened after protests nationwide over last month’s jailing of Alexei Navalny, a prominent critic of President Vladimir Putin.

Navalny and his supporters say his 30-month sentence, for alleged parole violations related to an embezzlement case, was trumped up for political reasons, something the authorities deny.

Google declined to comment on the Interfax report. Facebook, Twitter, Tiktok and Telegram did not immediately respond to requests for comment.

The cases against Google, Facebook and Twitter will be heard on April 2, the agency said.