Newsweek political writer Kurt Eichenwald is demanding that Twitter help unmask an anonymous tweeter who sent him a strobe light video with the intent of triggering a seizure.

Eichenwald, who has epilepsy, was apparently targeted for his reporting on Donald Trump and his foreign business interests. After appearing on Fox News for an interview with Tucker Carlson, Eichenwald says Twitter user @jew_goldstein sent the video with the message, “you deserve a seizure for your posts.”

Eichenwald claims the tweeter knew the video was meant to trigger seizures in people with his condition, and succeeded, which means Twitter was allegedly used as a means to commit assault.