Facebook said on Monday that it had blocked 115 accounts that police warned could be linked to "foreign entities" trying to interfere in the US midterm elections.
"On Sunday evening, law enforcement agencies on an Internet activity that they discovered recently and believed it might be linked to foreign entities," said Nathaniel Gleacher, director of e-security policy at Facebook.
"We immediately withheld these accounts and conduct a detailed investigation."
The investigation revealed so far about 30 accounts on Facebook and 85 on Instagram, which appear to be linked to "unreliable, coordinated behavior," Glischer said.
He added that all Facebook pages associated with these accounts appeared to be in either French or Russian.
The Entgram accounts, which were obscured, were mostly in English, some focused on "celebrities and others on political debate."
The announcement came shortly after US law enforcement and intelligence agencies called on citizens to be wary of Russian attempts to spread false news on the eve of Tuesday's election.
A study published last week showed that misinformation about social media was spreading at much higher rates than before the 2016 presidential election, which accused Russia of manipulating its results.
"But just a day after important elections in the United States, we wanted people to know about the action we've taken and the facts we know so far," Glischer said.
On Saturday, Twitter announced that it had deleted an "account group" that tried to share false information without giving a specific number.
Facebook, which has been accused of failing to do enough to prevent Russia and others from spreading misleading information during the presidential election in 2016, is seeking to send a message to the world that it is taking steps to prevent it from repeating.
Several weeks ago, it opened a "war room" at its headquarters in Menlo Park, California, to launch its war against misinformation and manipulation by outsiders trying to influence elections in the United States and elsewhere.
