Published: Oct 17, 2012 5:24 PM EDT
Updated: Oct 18, 2012 6:31 AM EDT

NEW YORK (AP) - A 21-year-old man arrested on charges he plotted to blow up the Federal Reserve building in New York City has appeared in federal court and been ordered held without bail.

Quazi Nafis was arrested Wednesday morning after a sting operation. Authorities say he parked a van filled with what he believed were explosives outside the building and tried to detonate it.

But his associates were actually undercover officers who arrested him at the scene - and the bomb was not real.

Wearing a brown T-shirt and black jeans, Nafis did not enter a plea during a brief court appearance Wednesday afternoon in Brooklyn. His defense attorney had no comment outside court.

Federal prosecutors say the man was monitored closely by the FBI and members of the Joint Terrorism Task Force, and the public was never in danger.