Facebook's chief security officer says an internal investigation shows an advertising operation likely out of Russia tried to "misuse the platform," over a two year period.

FOX's Jessica Rosenthal reports:

Facebook chief security officer Alex Stamos wrote in a post that roughly $100,000 was spent on 3,000 ads from June 2015 to mid 2017. Those ads were connected to 470 inauthentic accounts and pages and Facebook says they were likely operated out of Russia.

Stamos explains most of these ads and accounts didn't reference the election, but were instead used to make divisive social and political messages that he says were across the ideological spectrum. A quarter of the ads were geographically targeted.

Stamos says the fake accounts and ads have been removed and they've since begun looking at how to develop new techniques to detect fake accounts and ads while they're being created.

Jessica Rosenthal, FOX News.

Follow Jessica Rosenthal on Twitter: @JessicaFOXNews