Facebook on Thursday said it shut down 251 accounts for breaking rules against spam and coordinated deceit, some of it by ad farms pretending to be forums for political debate.
The move came as the leading social network strives to prevent the platform from being used to sow division and spread misinformation ahead of US elections in November.
Facebook removed 559 pages and 251 accounts that consistently violated rules against spam and "coordinated inauthentic behavior," according to an online post by cybersecurity policy chief Nathaniel Gleicher and product manager Oscar Rodriguez.
"Many were using fake accounts or multiple accounts with the same names and posted massive amounts of content across a network of Groups and Pages to drive traffic to their websites," they said.
"Many used the same techniques to make their content appear more popular on Facebook than it really was."
Other pages and accounts shut down were "ad farms" using Facebook to trick people into thinking they were forums for legitimate political debate, according to Gleicher and Rodriguez.
Facebook is getting a "war room" up and running on its Silicon Valley campus to quickly repel efforts to use the social network to meddle in upcoming elections in the US and Brazil.
Teams at Facebook have been honing responses to potential scenarios such as floods of bogus news or campaigns to trick people into falsely thinking they can cast ballots by text message, according to executives.
Facebook is keen to prevent the kinds of voter manipulation or outright deception that took place ahead of the 2016 election the brought US President Donald Trump to office.
Facebook is better prepared to defend against efforts to manipulate the platform to influence elections and has recently thwarted foreign influence campaigns targeting several countries, chief executive Mark Zuckerberg said recently in a post on the social network.
Facebook has started showing who is behind election-related online ads, and have shut down accounts involved in coordinated stealth influence campaigns.
With the help of artificial intelligence software, Facebook blocked nearly 1.3 billion fake accounts between March and October of last year, according to the social network.-AFP