But the bomb was bogus, and Nafis discovered he was the target of a law enforcement sting.
He is charged with attempting to use a weapon of mass destruction and attempting to provide material support to al Qaida. Nafis did not enter a plea at his arraignment, and he is being held without bail.
LINK: READ CRIMINAL COMPLAINT
His lawyer left court, brushing past reporters and refusing to comment on the case.
Prosecutors say Nafis came to this country in January on a student visa and immediately set about finding inspiration and accomplices online.
What he landed was an FBI informant and an undercover FBI agent, as well as the start of 24/7 monitoring. The FBI says Nafis had a list of targets, but finally settled on the Federal Reserve in the financial district.
"It makes the Federal Reserve bank, it gives it a position on our list of iconic targets here in New York City," NYPD Commissioner Ray Kelly said. "This individual came here with the express purpose of committing a terrorist attack. He was motivated by al Qaida. We see this threat as being with us for a long time to come."
The FBI says Nafis helped assemble the bomb at a warehouse and then drove it to right outside the Fed, near the World Trade Center. Then, he walked to the Millennium Hotel, and from a room with a view of his target, he had the undercover agent videotape his attack message.
"We will not stop until we attain victory or martyrdom," he said in the video.
Then, Nafis used his cell phone to detonate the bomb, only the FBI had already rendered the explosives inert.
Kelly says regardless of that, the threat was very real.
"When you go and pick up 50 20-pound bags of ammonium nitrate, and you obtain a truck and you bring it to the site of a major federal facility and you try and detonate it, that goes way past aspirational to me," Kelly said.
Agents with the Department of Homeland Security spent the day removing box after box from Nafis' apartment in Jamaica. Documents and other belongings were hauled away in a very public sweep.
"It's really scary to know that he lived right next door to us," one neighbor said.
Nafis lived with four other people in a second-floor apartment at the intersection of 93rd Avenue and 172nd Street. Before moving to Queens, he spent the spring semester at Southeastern Missouri State University, studying cyber security. He was reportedly the vice president of the Muslim Student Association on campus, and his background is among the long list of concerns for stunned neighbors.
"Especially since he's Bengali," neighbor Lamia Sikdr said. "And I am too. It brings us in a bad position. People will have this stereotype because of this incident."
Nafis is a banker's son from a middle class neighborhood, and family members said Thursday that they were stunned by his arrest.
The Federal Reserve building is one of the most fortified structures in Lower Manhattan, but many what kind of toll could an explosion at the building have taken on the nation's economy?
What would the financial fallout be if the plot worked?
A Pace University finance professor says there would be some financial impact, but the effects wouldn't be as far-reaching as the suspect had hoped. That's because of measures put in place after September 11th.
Back in 2001, when the New York Stock Exchange and NASDAQ were forced to close, the Federal Reserve remained open and was able to add $100 billion in liquidity per day during the three days following the attack, to help avert a financial crisis.
(The Associated Press contributed to this story)
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