Story highlights Man also faces federal cyberstalking charge

Journalist says he suffered a seizure and received more flashing images

(CNN) An additional charge has been filed against a Maryland man accused of tweeting an animated strobe image to a journalist with epilepsy, prosecutors in Texas said Monday.

John Rayne Rivello, 29, was charged with aggravated assault with a deadly weapon, said Brittany Dunn with the Dallas County District Attorney's Office.

A grand jury referral said Rivello sent the tweet knowing journalist Kurt Eichenwald was "susceptible to seizures and that such animations are capable of causing seizures." The document said Rivello used "a deadly weapon, to wit: a tweet and a graphics interchange format (GIF) and an electronic device and hands during the commission of the assault."

Prosecutors said Eichenwald was chosen because Rivello had a bias against people of Jewish descent.

Eichenwald's attorney, Timothy Perkins, told CNN: "We consider the message like a bomb or sending anthrax to someone in the mail."

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