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The Russian government asked Google not to promote "illegal mass events" on YouTube after protesters took to Moscow's streets to demand free elections on Saturday, Reuters reported. State communications watchdog Roscomnadzor wasn't happy that people used YouTube push notifications to promote demonstration livestreams.

If the search giant doesn't respond to Roscomnadzor's letter, "the Russian Federation will regard this as interference in the sovereign affairs of the state, as well as a hostile influence and obstructing the holding of democratic elections," the watchdog said in a release, without specifying what action it would take.

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Saturday's protests saw tens of thousands of people taking to the streets of the Russian capital and other cities after some of the country's internet celebrities and musicians urged their millions of social media followers to attend the demonstrations, according to the Wall Street Journal.

It wasn't the first time Google's come under pressure from Roscomnadzor -- it reportedly tweaked its search results in Russia to remove blacklisted websites earlier this year, after being threatened with fines if it failed to do so. In 2018, Russia threatened to block YouTube and Instagram over content relating to an oligarch linked to Donald Trump's 2016 presidential campaign.

Google didn't immediately respond to a request for comment.

First published at 4:18 a.m. PT.

Updated at 4:50 a.m. PT: Adds more detail.