Facebook has purged more than 800 U.S. pages and accounts for spamming users with garbage links and clickbait.

Facebook has a policy banning coordinated "inauthentic behavior" - networks of accounts or Pages working to mislead others about who they are, and what they are doing. This year, the social network has enforced this policy against many Pages, Groups and accounts created to stir up political debate, including in the US, the Middle East, Russia and the UK.

One common type of spam has been posts that hawk fraudulent products like fake sunglasses or weight loss "remedies." But a lot of the spam has to do with networks of Pages using fake accounts or multiple accounts with the same names. They post clickbait posts on these Pages to drive people to websites that are entirely separate from Facebook and seem legitimate, but are actually ad farms. The people behind the activity also post the same clickbait posts in dozens of Facebook Groups, often hundreds of times in a short period, to drum up traffic for their websites. And they often use their fake accounts to generate fake likes and shares. This artificially inflates engagement for their inauthentic Pages and the posts they share, misleading people about their popularity and improving their ranking in News Feed.

Facebook said it removed 559 Pages and 251 accounts that have consistently broken its rules against spam and coordinated inauthentic behavior. 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. Many used the same techniques to make their content appear more popular on Facebook than it really was. Others were ad farms using Facebook to mislead people into thinking that they were forums for legitimate political debate.

Facebook also disabled dozens of accounts and profiles belonging to Russian database provider SocialDataHub for what it termed the unauthorized collection of user information.

Facebook said that SocialDataHub, which has previously provided analytical services to the Russian government, had violated its terms of use.

"As part of our efforts to protect people's security, we have recently removed SocialDataHub's accounts... because they were scraping people's information," it said.

"This is a violation of our terms of service, and we have disabled more than 66 of SDH's accounts, profiles, pages, and apps from our service," it added. "We expect to find and disable more."