Leon Traille, 29, said not a word today in U.S. District Court in Alexandria. Dressed in green jail shirt and pants, he stood silent, staring ahead, as judge Teresa Buchanan asked, "Mr. Traille - do you hear me, Mr. Trail?"
Traille faces a federal arson charge after Thursday's lunchtime drama at the Ballston Commons Mall food court.
Authorities say he threw a crudely made lighted Molotov cocktail "equipped with what appear to be wood matches taped to a brown glass bottle' into the food court - it never exploded - then went to the second-floor skyway area and dropped a bag containing three more devices.
No one was hurt in the incident but the mall was evacuated and business disrupted for hours.
Witnesses and mall security cameras led police and the FBI to arrest Traille, who was sitting at a table outside the mall, a short time later.
Traille, of no fixed address, appears to have lived in various states, including New York and Georgia.
He says on his linkedin site that he is a software engineer with a master's degree in computer science from the Georgia Institute of Technology who did contracting work at various firms, none for more than a few months.
Bloomberg confirmed Traille worked at its New York office for less than three weeks last year.
So far authorities are not speculating on a possible motive for such a brazen act.