The tone of this year’s presidential election has been exceptionally nasty, and each week seems to bring some new development in the race to sink to the absolute bottom. The latest bit of horrendous behavior comes from a Trump supporter who tweeted a Pepe the Frog video intended to cause seizures at a reporter who is known to be epileptic.

Newsweek‘s Kurt Eichenwald has been an outspoken critic of Trump and published an article in mid-September about how his ties would create major conflicts of interest were he to become president. A few weeks later, Eichenwald says he got a tweet from someone named “Mike’s Deplorable AF,” which had a video featuring “some sort of strobe light, with flashing circles and images of Pepe flying toward the screen.”

The tweet and video have been deleted, but he says it was clearly “epileptogenic,” which means its intended to give someone a seizure. That’s obviously a messed up thing to do to someone who you know is epileptic (and Eichenwald is very public about his epilepsy). Luckily, Eichenwald, who says he initially hit play on the video without thinking, did not end up having a seizure.

Even in the toxic sea that is Twitter, where many people are routinely harassed and threatened with death and rape, this stands out as a terrifying escalation. It’s the rare psycho who figures out how to weaponize Twitter to cause actual physical harm, and it’s hard to know where we have left to go from here — short of using social media to mobilize actual angry mobs to hunt down people they disagree with.