Facebook said Thursday it had removed hundreds of fake pages and accounts operating in Eastern Europe that were run by the Kremlin-linked news outlet Sputnik.

A separate network of inauthentic accounts operating in Ukraine and run by the infamous Russian troll factory had also been taken down, following a tip-off from U.S. law enforcement.

Facebook said more than 500 Facebook and Instagram accounts and pages were removed for “coordinated inauthentic behavior.”

The Sputnik-operated network posted a variety of content, including weather, travel and sports, but much of it was political and very anti-Western and anti-NATO, Facebook said.

The social media giant, which has come under significant pressure to do more to stop bad actors weaponizing its platform to spread disinformation, said the Sputnik accounts were part of a network that originated in Russia and operated in the Baltics, Central Asia, the Caucasus and Central and Eastern Europe.

Some 289 Facebook pages and 75 Facebook accounts associated with this network were closed. Almost 800,000 people were following one or more of those pages.

The pages spent a total of $135,000 on Facebook, paid for in euros, rubles and U.S. dollars, with the ads stretching back five years. The pages also organized around 190 events between August 2015 and January 2019.

Up to 1,200 people expressed interest in at least one of these events but Facebook said it could not confirm whether any of these events actually took place.

Conducted in collaboration with the Atlantic Council’s Digital Forensic Research Lab (DFRL), a Facebook investigation found that the people running these pages were not who they claimed to be.

“We found that these pages and accounts were linked to employees of Sputnik, a news agency based in Moscow and that some of the pages frequently posted about topics like the anti-NATO sentiment, protest movements, and anti-corruption,” Facebook said.

Sputnik is the main online media platform of Rossiya Segodnya, the Kremlin-owned media agency.

“This is the first time we’ve seen this sort of operation run by a state propaganda agency, amplifying its content by using inauthentic pages,” Ben Nimmo, an analyst with DFRL who has spent years watching Russian disinformation campaign, told VICE News. ”It suggests that Rossiya Segodnya, Sputnik’s parent company, is pushing hard to increase its online audience by overt and covert means.”

Facebook’s decision to remove these pages, accounts, and groups was not based on the content they were posting, but on who was doing the posting.

“We’re taking down these Pages and accounts based on their behavior, not the content they post. In these cases, the people behind this activity coordinated with one another and used fake accounts to misrepresent themselves, and that was the basis for our action,” Nathaniel Gleicher, Facebook’s head of cybersecurity policy, said in a blog post.