(AP) - A Bangladeshi man who came to the United States to wage jihad was arrested in an elaborate FBI sting on Wednesday after attempting to blow up a fake car bomb outside the Federal Reserve building in Manhattan, authorities said.

Before trying to carry out the alleged terrorism plot, Quazi Mohammad Rezwanul Ahsan Nafis went to a warehouse to help assemble a 1,000-pound bomb using inert material, according to a criminal complaint. He also asked an undercover agent to videotape him saying, "We will not stop until we attain victory or martyrdom," the complaint said.

Agents grabbed the 21-year-old Nafis - armed with a cellphone he believed was rigged as a detonator - after he made several attempts to blow up the bomb inside a vehicle parked next to the Federal Reserve, the complaint said.

Authorities emphasized that the plot never posed an actual risk. However, they claimed the case demonstrated the value of using sting operations to neutralize young extremists eager to harm Americans.

"Attempting to destroy a landmark building and kill or maim untold numbers of innocent bystanders is about as serious as the imagination can conjure," said Mary Galligan, acting head of the FBI's New York office. "The defendant faces appropriately severe consequences."

Nafis appeared in federal court in Brooklyn to face charges of attempting to use a weapon of mass destruction and attempting to provide material support to al-Qaida. Wearing a brown T-shirt and black jeans, he was ordered held without bail and did not enter a plea. His defense attorney had no comment outside court.

The defendant had sought assurances from an undercover agent posing as an al-Qaida contact that the terrorist group would support the operation.

"The thing that I want to do, ask you about, is that, the thing I'm doing, it's under al-Qaida?" he was recorded saying during a meeting in bugged hotel room in Queens, according to the complaint.

In a September meeting in the same hotel room, Nafis "confirmed he was ready to kill himself during the course of the attack, but indicated he wanted to return to Bangladesh to see his family one last time to set his affairs in order," the complaint said.

But there was no allegation that Nafis actually received training or direction from the terrorist group.

Prosecutors say Nafis traveled to the U.S. on a student visa in January to carry out an attack. In July, he contacted a confidential informant, telling him he wanted to form a terror cell, the criminal complaint said.

In further conversations, authorities said Nafis proposed several spots for his attack, including the New York Stock Exchange - and that in a written letter taking responsibility for the Federal Reserve job he was about to carry out, he said he wanted to "destroy America." Other communications took place through Facebook, the complaint said.