The company says that the IRA employed more than a thousand people to engage in electronic disinformation campaigns around the world using fake social media accounts. It also reports that the IRA-linked Tumblr accounts were only focused on the US and weren't advertising, but rather organic content. In response, the company will email everyone who liked, reblogged, replied to or followed an IRA-linked account with the usernames included.

The company will continue to monitor its service for similar activity in the future, and will take the same steps if it finds evidence of such. Ultimately, though, Tumblr says that it's also the general public's responsibility to be aware of the possibility of this sort of disinformation and remain skeptical.