Diffusion network for the article titled “Spirit cooking: Clinton campaign chairman practices bizarre occult ritual,” published by the conspiracy site Infowars.com four days before the 2016 U.S. election.

Shad and co say bots play a particularly significant role in the spread of fake news soon after it is published. What’s more, these bots are programmed to direct their tweets at influential users. “Automated accounts are particularly active in the early spreading phases of viral claims, and tend to target influential users,” say Shao and co.

That’s a clever strategy. Information is much more likely to become viral when it passes through highly connected nodes on a social network. So targeting these influential users is key. Humans can easily be fooled by automated accounts and can unwittingly seed the spread of fake news (some humans do this wittingly, of course). —MIT Technology Review