The Federal Bureau of Investigation arrested a Twitter user Friday for allegedly causing Newsweek writer Kurt Eichenwald to have a seizure.

The suspect, John Rivello, was arrested by the FBI at his Maryland home. Rivello, 29, is being charged under a federal cyberstalking statute and will appear in federal court in Dallas Monday.

The Twitter incident occurred in December 2016 when an account with the username “Ari Goldstein” or “@jew_goldstein” sent Eichenwald a gif, which is an animated image, with changing colors that said, “you deserve a seizure.”

Eichenwald’s account subsequently tweeted, “@jew_goldstein This is his wife, you caused a seizure. I have your information and have called the police to report the assault.”

An FBI affidavit says that Rivello told other Twitter users over direct message he knows Eichenwald suffers from epilepsy and that he hopes the gif “sends him into a seizure.” A search warrant also found that Rivello took a screenshot of a Wikipedia page that had been altered to show that Eichenwald died on the day of the Twitter interaction.

Peter Stephenson, an expert in cyber criminology, previously told TheDC that “one could say that the tweet constituted an assault.” “What Mr. Rivello did with his Twitter message was no different from someone sending a bomb in the mail or sending an envelope filled with Anthrax spores,” Eichenwald’s attorney Steven Lieberman told Newsweek.

The Newsweek writer identified who the alleged perpetrator was in January. He tweeted Friday, “After a 3 month investigation, the FBI this morning arrested the man who assaulted me using a strobe on twitter that triggered a seizure.”

“He currently faces federal charges & is expected to also be indicted by the Dallas District Attorney on different charges in next few days,” Eichenwald added.