A Muslim convert was indicted on charges of trying to use hand grenades to blow up garbage cans at a shopping mall.
Derrick Shareef, 22, was arrested December 6 by an FBI-led anti-terrorism task force following a sting operation in which an undercover informant secretly tape-recorded his plans.
Federal prosecutors who announced the arrest said they were convinced Shareef had operated alone and there had been no danger to the public.
Shareef is being held in the government's Metropolitan Correctional Center pending a court hearing. No date has been set.