Meta says it has removed networks of fake accounts stirring tensions at the border between Poland and Belarus.
A number of fake profiles were linked to the Belarusian State Security service (KGB), the big tech giant said.
Meanwhile, a number of fake Facebook accounts in Poland also targeted Iraqi users and tried to discourage migrants from entering the European Union.
The pages were all removed by Meta for violating policies on "co-ordinate inauthentic behaviour".
For weeks hundreds of migrants have been trapped at the EU's external frontier amid a political dispute between the bloc and Belarus. Rights groups say 13 people have died amid worsening weather conditions.
Brussels has accused Minsk of encouraging migrants to cross the border to destabilise the bloc in retaliation against EU sanctions. Belarus has rejected the allegations.
'Links to the Belarusian KGB'
On Wednesday, Meta -- the parent company of Facebook -- said it had uncovered dozens of fake Belarusian accounts posing as journalists and activists.
The accounts criticised Warsaw and posted content about "Polish border guards allegedly violating migrants' rights," the company said in its monthly report.
Some of the accounts had also used artificial intelligence to generate photos for their profiles. Meta said the network targeted audiences in the Middle East and Europe, posting in English, Polish, and Kurdish.
"Although the people behind it attempted to conceal their identities and coordination, our investigation found links to the Belarusian KGB," it said.
A total of 41 Facebook accounts, five Facebook groups, and four Instagram accounts linked to the network have now been removed. Meta says fewer than 1,400 people joined the Facebook groups while fewer than 200 accounts followed the Instagram pages.
The Belarusian KGB has not commented on the Meta report.
Other accounts posed as migrants
Meanwhile, Meta said it has also identified dozens of fake accounts in Poland that had also attempted to stoke tensions at the border.
The company separately removed 31 Facebook accounts, four groups, two Facebook Events, and four Instagram accounts that had targeted users in Belarus and Iraq. But Meta did not say that the network of fake accounts was linked to the Polish state or security officials.
Most of the fake accounts posed as migrants, claiming to share their own negative experiences of trying to cross the border from Belarus to Poland, or migrants' difficult lives in Europe.
"They also posted about Poland’s strict anti-migrant policies and anti-migrant neo-Nazi activity in Poland," Meta said.
One of the fake accounts -- which also used an artificially-generated profile photo -- had also planned a Minsk protest on a Facebook event page, which was later reported by local media.
"This network appeared to operate across multiple platforms, including by reposting YouTube videos on Facebook, to dissuade migrants from entering the EU," Meta said.
"They also shared links to news articles criticizing the Belarusian government’s handling of the border crisis and off-platform videos alleging migrant abuse in Europe."
'Distinct violations of our security policies'
Meta has been under global pressure from regulators to combat disinformation networks on its platform.
"The global threats we tackle have significantly evolved since we first started sharing our findings," the company said on Wednesday.
As part of its monthly report, Meta also said it had taken action a disinformation network in China that had spread disinformation on Facebook about COVID-19.
The fake accounts had amplified content from a made-up Swiss biologist, who had claimed that the United States was lobbying the World Health Organisation to blame China for the pandemic. Chinese state media later quoted the fake expert.
The network was exposed when Swiss authorities announced in August that they had no record of any such biologist.
Meta also said it had taken action against a number of Facebook accounts in Italy and France that had "targeted medical professionals, journalists, and elected officials with mass harassment".
"Our goal over time is to make these behaviors more costly and difficult to hide, and less effective," Meta said.