NEW YORK (AP) — Federal authorities have arrested a man they say was plotting to blow up the Federal Reserve building in New York City, just blocks from the World Trade Center site.

Authorities say 21-year-old Quazi Nafis was arrested Wednesday morning after a sting operation that involved the FBI and New York Police Department. The suspect 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.

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